Appendices – Table of contents - KU Leuven · Appendices – Table of contents Appendix 1 - Stratigraphy of the Late Cretaceous deposits: previous work ... named Volcanismo tardío

Appendices – Table of contents

I

Appendices – Table of contents Appendix 1 - Stratigraphy of the Late Cretaceous deposits: previous work ........................................... 1

1.1 The Piñón Formation..................................................................................................................... 1 1.2 The Las Orquídeas unit ................................................................................................................. 3 1.3 The Calentura Formation............................................................................................................... 4 1.4 The Cayo Formation...................................................................................................................... 6 1.6 The Guayaquil Formation ........................................................................................................... 13

Appendix 2 - Field and sample locations .............................................................................................. 19

Appendix 3 - Methodology for mineralogical characterization .............................................................19

3.1 Sample preparation for X-ray diffraction .....................................................................................19

3.2 Methodology for cation exchange capacity measurements of zeolitic rocks ...............................20

3.3 Staining of feldspars & zeolites....................................................................................................23

3.4 Digestion of silicate rock samples: LiBO2 fusion in graphite crucible for AAS and ICP-MS

analysis ...............................................................................................................................................25

Appendix 4 - Mineralogical characterization of the Late Cretaceous Deposits .................................... 27

4.1 Structures used in the Rietveld refinement.................................................................................. 27

4.2 XRD quantifications.................................................................................................................... 33

4.2.1 Río Guaraguao section (samples are ordered from the base to the top of the section)

.....................................................................................................................................33

4.2.2 Guayaquil (samples are ordered from the base to the top of the section) ...............41

4.2.3 Río Derecha - Río Zamoreño................................................................................46

4.2.4 Manabí área .........................................................................................................47 4.3 EPMA.......................................................................................................................................... 49

4.3.1 HEU-type zeolites ................................................................................................49

4.3.2 Mordenite ............................................................................................................55

4.3.3 Laumontite...........................................................................................................56

4.3.4 Chlorite-Smectite .................................................................................................57

4.3.5 Celadonite............................................................................................................60 4.4 SEM-EDX ................................................................................................................................... 61

4.4.1 Heu-type zeolites .................................................................................................61

4.4.2 Mordenite ............................................................................................................62

4.4.3 Analcime..............................................................................................................63

4.4.4 Chlorite/smectite ..................................................................................................64

4.4.5 Plagioclase ...........................................................................................................65

4.4.6 Pyroxene ..............................................................................................................69 4.5 ICP-OES...................................................................................................................................... 70

Appendix 5 - Terrain observations and petrogrophical analyses of the volcanic components, structures

and textures of the samples of the Río Guaraguao section.................................................................... 73

5.1 The Piñón and Calentura Formations .......................................................................................... 73

5.1.1 The Piñón Formation............................................................................................73

5.1.2 The Calentura Formation......................................................................................73 5.2 The lower unit of the Cayo Formation (Río Guaraguao unit) ..................................................... 74

5.2.1 Coarse breccia at the base of the Cayo Formation.................................................74

5.2.2 The basal part of the lower unit ............................................................................76

5.2.3 The middle part of the lower unit .........................................................................76

5.2.4 The upper part of lower unit .................................................................................80

Appendices – Table of contents

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5.3 The upper unit of the Cayo Formation ........................................................................................ 81

5.3.1 The base of the upper unit of the Cayo Formation ................................................81

5.3.2 The lower part of the upper unit of the Cayo Formation .......................................82

5.3.3 The middle part of the upper unit of the Cayo Formation......................................83

5.3.4 The upper part of the upper unit of the Cayo Formation .......................................85

Appendix 9 - Petrographical analyses of the alteration of the samples of the Río Guaraguao section . 89

9.1 Alteration in the Piñón Formation............................................................................................... 89

9.2 Alteration in the Calentura Formation......................................................................................... 89

9.3 Alteration in the lower unit of the Cayo Formation .................................................................... 89

9.3.1 Coarse breccia at the base of the Cayo Formation.................................................89

9.3.2 Lower part of the lower unit .................................................................................89

9.3.3 Middle part of the lower unit ................................................................................90

9.3.4 Upper part of the lower unit .................................................................................97 9.4 Alteration in the upper unit of the Cayo Formation .................................................................. 100

9.4.1 The lower part of the upper unit .........................................................................100

9.4.2 The middle part of the upper unit .......................................................................102

9.4.3 The upper part of the upper unit .........................................................................103

Appendix 1 – Stratigraphy of the Late Cretaceous deposits – previous work

1

1.1 The Piñón Formation

Early investigations

The formation was first recognized by Wolf

(1892 – in Goossens and Rose, 1973), who

named the rocks: “Grunstein formation”. The name Piñón was first introduced by Tschopp

(1948 – in Goossens and Roose, 1973), who

named the formation after its type locality in

the Río Piñón, 20 km southwest of Portoviejo

in the Manabí area. Sauer (1965 – in Goossens

and Rose, 1973) defines the Piñón Formation

as a series of basaltic lavas, diabases,

pyroclastic rocks, gabbros and diorites

Bucaram (1966) describes the Piñón Formation

in the region of Guayaquil, where it consists of

diabase flows which become amygdaloidal

higher in the section. A few thin tuff and tuffaceous sandstone beds are found

interbedded with amygdalar diabase. The

upper part of the formation is essentially a light

green, finely crystalline basic igneous

porphyry with interbedded tuffaceous shale

and gray to cream and reddish-coloured,

tuffaceous and siliceous siltstone. It is locally

intruded by granodiorites. Bucaram (1966)

attributes a Jurassic to Cretaceous age to the

Piñón Formation, but has no fossil or

radiometric data to prove this.

The basic igneous complex

Goossens and Rose (1973) present the results

of an aeromagnetic and radioactive survey of

1964–1965 performed by the UNDP. The

author’s state that the Piñón Formation

corresponds to a complex of so many different

lithologies and ages that the whole mafic-rock

sequence in the Ecuadorian coastal plain can

best be classified as a basic igneous complex

(Goossens, 1970 – in Goossens and Rose,

1973). Included in the basic igneous complex

are the rocks with the same lithologies

cropping out along the western slopes of the

Western Cordillera, called Formación

Diabásica–Porfirítica by Sauer (1965 – in

Goossens and Rose, 1973) and ultramafic

rocks in Colombia. The rocks are submarine

effusions overlying (or intruded by) coarse

grained rocks (gabbro-harzburgite) and

intruded by diorite-tonalite bodies representing

the products of differentiation of the same

basaltic magma (Goossens, 1968 – in

Goossens and Rose, 1973).

The basic igneous complex was divided in two

members by Goossens and Rose (1973): The

lower member, equivalent to the Piñón sensu

stricto formation, was explained as a principal

phase of magmatism represented by fine

grained, hypabyssal, and coarse grained

ultramafic to intermediate rocks, which were

emplaced some time after the Middle Jurassic and before the end of the Cretaceous. This

magmatic phase includes harzburgite bodies,

diabase, gabbro and basalt. The upper member

is composed of effusive phases of younger

tholeiites erupted along east-trending fractures

and occurred during the Late Cretaceous until

the early Eocene.

Because of the tholeiitic character of the rocks,

Goossens et al. (1977) state that the basic

igneous complex was either formed at an

oceanic ridge, or in an immature island arc.

The suite is clearly bimodal (high Ca basalt

and low Ca basaltic andesite) and formation of

the basaltic andesites by fractional

crystallization of the basalts can be ruled out.

Geochemical data seem in general to support

an ocean floor tholeiite interpretation for the

rocks, but the higher concentration of K2O and

Sr and the relative prominence of andesites are

features of the chemistry that are not consistent

with this conclusion. The authors suggest that

there is perhaps no sharp distinction between

ocean floor tholeiites and these tholeiites

developed in “youthful” island arcs. No

APPENDIX 1 - STRATIGRAPHY OF THE LATE

CRETACEOUS DEPOSITS: PREVIOUS WORK

Appendix 1 – Stratigraphy of the Late Cretaceous deposits: previous work

2

distinction has been made between the lower

and upper member in the geochemical

analyses.

On the 1:100 000 geological maps of the Costa

published in 1974 and 1975 the name basic

igneous complex was used for the Piñón

Formation and all other effusive volcanic rocks

regardless of their age, which lead to a lot of

misinterpretations. In most later publications,

no distinction is made between the Piñón sensu

stricto formation and later effusive volcanic

rocks (e.g., Wallrabe-Adams, 1990;

Marksteiner and Aleman, 1990).

Piñón Formation sensu stricto

Feininger and Bristow (1980) proposed to use

the name Piñón for the pre–Cayo volcanic

rocks of the coastal region only. According to

them, a continuous series of the Piñón

Formation occurs in the Cordillera Chongón–

Colonche, while a discontinuous series can be

found near the Coast of Portoviejo, between

Portoviejo and Esmeraldas, and southeast of

Esmeraldas. Small exposures of the formation

on the Santa Elena Peninsula are described as olistoliths. Next to basalt and diabase, they

also include basaltic agglomerate and tuff, and

sparse and thin layers of argillite and wacke in

the Piñón Formation (Carnfield, 1966 in

Feiniger and Bristow, 1980).

Feininger (1986) defines the Piñón terrane as

an area of 62000 km2 between the Romeral

fault and the Pacific coast extending

northwards into Colombia for an unknown

distance. All basement of the Piñón terrane is

formed by the Piñón Formation. The most

remarkable feature of the Piñón terrane is its

huge positive simple Bouguer gravity anomaly

where the Piñón Formation crops out or where

it is covered only thinly by younger rocks.

Anomalies in the town of Daule, 45 km

northwest of Guayaquil, reach +179 mGal (1

mGal = 10 µm s-1

) and are the largest on-land

positive anomalies recognized in the western

hemisphere, at the time when the article was

written. Anomalies over a surrounding area of

6000 km2 exceed +100 mGal. Such large

positive anomalies demonstrate the oceanic

nature of the Piñón Formation and confirm that

it is not underlain by continental crust.

Santos and Alvarado (1989) state that the

Piñón Formation (sensu stricto) only occurs in

the Cordillera Chongón–Colonche. The

majority of the rocks occurring in the Manabí

and Borbón basins belong to a later volcanism

named Volcanismo tardío de Cayo by the

authors.

Lebrat et al. (1987) refer to cumulate gabbros

associated with the Piñón dolerites in a hill

three kilometres northeast of Cerro de

Masvale, near Guayaquil. North of Guayaquil,

isolated outcrops of peridotites, among them

the Pascuales harzburgite, occur. Pillow lavas

range from aphyric to porphyritic, containing

phenocrysts of plagioclase, clinopyroxene and

Fe-Ti oxides. Massive fine grained dolerites

contain the same mineral phases but display

intersertal or ophitic texture. Pervasive

hydrothermal alteration and mineralization

(Fe-Cu sulphides) are common in both basalts

and dolerites, and low-grade metamorphism of

zeolite, pumpellyite-prehnite, and in some case

greenschist facies have been reported (Lebrat

et al., 1985).

The age of the Piñón Formation Mamberti et al. (2003) and Kerr et al. (2003)

state that the Piñón Formation in the Guayaquil

area is older than 90 Ma or even older than 95

Ma because it is overlain by arc-derived

sediments of Turonian and Cenomanian age.

However, later dating (see Calentura

Formation) shows that these sediments are of

Middle Coniacian age (Ordóñez, 2003, 2005;

Ordóñez et al., 2006; Mendoza and Velasco,

2003).

Van Melle et al. (2008) investigate cherts

between pillows in the upper part of the Río

Guaraguao section. They yield the planktonic

foraminifera Hedbergella holmdelensis

(Coniacian–Maastrichtian), and the

radiolarians Cryptamphorella sp.,

Orbiculiforma sp., Praeconocaryomma sp.,

Spongosicus sp., Theocampe tina and

Theocampe ascalia, associated with

palynomorphs (Cicatricosisporites sp.,

Psilatricolporites sp.). The association of

Hedbergella holmdelensis, Theocampe ascalia

and Theocampe tina suggests an age comprised

within the Coniacian – Middle Campanian

interval. This means that the Piñón Formation

has to be of Early to Middle Coniacian age, as


3

the Calentura Formation is of Middle

Coniacian age (Ordóñez 2003, 2005; Ordóñez

et al., 2006; Mendoza and Velasco, 2003).

Early radiometric dating was performed in the

Manabí area where it is not possible to know if

the measured rocks are from the Piñón

Formation or from more recent volcanics.

Snelling (1970 – in Goossens and Roose,

1973) obtains dates of the basic igneous

complex of 72, 85 and 104 Ma by K/Ar dating.

Kennerly (1980) dates the Piñón Formation as

113±10 Ma and, 107±15 Ma in the Manta

region.

Luzieux et al. (2006) analysed a gabbro located

near the town of Nobol (UTM coordinates:

610094; 9787726, WGS84). They obtained a

plateau hornblende 40

Ar/39

Ar age of 88.8 ± 1.6

Ma from a gabbro. The chondrite-normalized

plot of the rare earth elements shows a flat

pattern, which is comparable to previously

published data of the Piñón Formation and

confirms the stratigraphic attribution of the

investigated sample to the Piñón Formation.

Origin of the Piñón Formation

The Piñón Formation was interpreted as a

remnant of oceanic basement or as primitive

oceanic island arc tholeiites. The interpretation

as an oceanic arc is mainly because a lot of

samples were measured in the Manabí area,

and these samples probably belong to younger

formations and not to the Piñón Formation.

Reynaud et al. (1999) interpret the Piñón

Formation as the remnants of an oceanic

plateau, similar as did other authors in

Colombia (e.g., Kerr et al., 1997). Kerr et al.

(2003) confirm that the Piñón Formation is

part of an oceanic plateau and state that it is

geochemically very similar to the Pallatanga

unit in the western Cordillera. This is

confirmed by Vallejo et al. (2006) who obtains

similar radiometric ages for the Pallatanga unit

as Luzieux (2006) does for the Piñón unit.

The geochemical and age similarities of the

Piñón unit with other units in the Cordillera

Occidental of Ecuador, in Colombia and in the

Caribbean, suggest that all these fragments are

derived from the same oceanic plateau

(Reynaud et al., 1999, Mamberti et al., 2003;

Kerr et al., 2002, 2003; Luzieux et al., 2006;

Luzieux, 2007; Vallejo et al., 2006).

Luzieux (2007) performs paleomagnetic

measurements on sample of the oceanic

plateau basement in the Piñón block. From this

study it can be concluded that the oceanic

plateau was formed around equatorial latitudes,

making it possible that the Galápagos hotspot,

which lays at equatorial latitudes, formed the

oceanic plateau.

1.2 The Las Orquídeas unit

“The arco Cayo”

The Las Orquídeas unit was previously named

as “arco Cayo” by Benítez (1995). It occurs

between Guayaquil (Pascuales) and the Río

Bachillero in the Cordillera Chongón–

Colonche. It occurs on top of the Piñón

Formation and consists of basaltic andesitic

porphyritic pillow lavas, columns, lava flows and volcanic breccia. They are altered to

smectite, chlorite, calcite and locally epidote

and pumpellyite, which are interpreted as

marine alteration during its deposition by

Benítez (1995).

The name “Las Orquídeas” was introduced by

Reynaud et al. (1999) as: “Las Orquídeas

member of the Piñón Formation” but, has lead

to a lot of confusion ever since. Reynaud et al.

(1999) use the name for “a thin layer of

pillowed phyric basalts” overlying the Piñón

Formation in the neighbourhood of Las

Orquídeas in Guayaquil and in the Cordillera

Chongón–Colonche. Luzieux et al (2006) also

include mafic intrusions in the Guayaquil

region and name the unit: “Las Orquídeas

Formation”. Luzieux (2007) states that the

Cayo Formation should strictly refer to

sedimentary rocks and hence the volcanic

rocks located proximal to Guayaquil are

assigned to the Las Orquídeas formation.

Luzieux (2007) also places the stratigraphic

position of the Las Orquídeas unit in doubt,

because the contact with overlying formations

is not exposed in outcrop. Reynaud et al.

(1999) argue that in the type locality, which no

longer exists, pillow basalts of the Las

Orquídeas formation are conformably overlain

by the Calentura Formation. However, a

previous study by Benítez (1995) states that no


4

pillows were present at the type locality.

Consequently, the samples referred to by

Reynaud et al. (1999) may have been collected

from an intrusive body, and unfortunately the

issue will never be resolved due to the

destruction of the outcrop (Luzieux, 2007).

Benítez (1995) investigates the geochemistry

of the rocks of the arco Cayo and, interprets

them as tholeiitic orogenic basalts. Reynaud et

al. (1999) investigate the geochemistry of two

samples of the Las Orquídeas member. One

has calc-alkaline affinities, while the other is

arc-tholeiitic. The rocks are LREE–enriched

and their N–MORB normalized diagrams are

very similar to those of orogenic suites. They

have a negative Nb–Ta anomaly, similar to

arc-related rocks. They have very low levels of

Y and HREE, suggesting the presence of

residual garnet in the mantle source.

Volcanic breccias covering the Piñón

Formation

Several authors demonstrate the presence of

volcanic breccia covering the Piñón Formation.

Wolff (1874 – in Labrousse, 1989) and Bristow (1977 – in Labrousse, 1989) include

these rocks in the Piñón Formation, but

Labrousse (1986) includes them in the

Calentura Formation. According to Labrousse

(1986), these breccias occur localized along

the Cerro Germania north of Guayaquil which

has the morphology of a caldera. At the base, a

mélange occurs of tholeiitic basalt blocks,

andesite or diorite bodies which are later

intrusions, pyroclastic flow deposits, welded

tuffs, coarse well cemented tuffs, blocks with

coarse ferruginous nodules (1–2 cm)

containing quartz. The contact of this part of

the Calentura Formation with the “real

Calentura Formation” is made up of a unit of

Piñón rocks rich in barite and authigenic

quartz.

Santos and Alvarado (1989) demonstrate the

presence of volcanic breccias composed of

basaltic or basaltic andesitic clasts on top of

the Piñón Formation in the Estero Arenoso,

near Guayaquil. Similar breccias are described

in the Río Guaraguao, overlying the Piñón

Formation (Vilema, 2004a, 2008). Van Melle

et al. (2008) define the name: “Las Orquídeas

member of the Calentura Formation”, for the

andesitic volcanic breccia overlying the Piñón

Formation along the Cordillera Chongón–

Colonche. Vilema (2004a, 2008) and Van

Melle et al. (2008) observe these volcanic

breccias both below and above the typical fine

grained beds of the Calentura Formation. The

relation of these breccias with the Las

Orquídeas unit of Reynaud or the Las

Orquídeas formation of Luzieux (2007) is

unclear.

Van Melle et al. (2008) investigate the

geochemistry of the breccia of: “Las Orquídeas

unit of the Calentura Formation” in the Río

Guaraguao. At the base of the formation, the

lavas have moderate Mg content (3.83–5.6

wt%), the rare elements diagram normalized to

chondrites exhibits a flat pattern, but multi-

elementary diagrams, normalized to primitive

mantle, exhibit negative anomalies for Nb and

Ta for all rocks, evidencing a magmatic arc.

Higher in the sequence, the lavas have lower

Mg content (1.3–1.9 wt%) are moderately

alkaline (5.18–7.26 wt% [Na2O + K2O]) and,

have high Si contents (> 60% wt%), displaying

features of andesites to dacites. The REE plot

normalized to chondrites exhibit light REE

enrichments and a flat pattern for heavy REE. Van Melle et al. (2008) interpret the Las

Orquídeas member as tholeiitic arc lavas,

which evolve to calc-alkaline series through

time. Another possibility is that they are

formed by partial melting of deeper parts of the

underlying oceanic plateau, as proposed by

Haase et al. (2005) for arc-lavas associated

with mid-oceanic ridges.

Allibon et al. (2008) investigates the same

rocks in the Guaraguao and Derecha rivers.

They contribute the high Mg content (6–11.5

wt%), the LREE enrichment and the high

percentage of clinopyroxene to a high

percentage of partial melting at the magmatic

source. The origin of the LREE enrichment can

be due to subduction of pelagic sediments.

They suggest an anomalous thermal regime

responsible for the high partial melting of the

plateau, which was relatively young when

subduction started (a few Ma).

1.3 The Calentura Formation

History


5

Thalmann (1946) defines the Calentura

member as the basal part of the Cayo

Formation. He defines the type locality as an

old quarry at Calentura, on the east side of the

Guayas River near Guayaquil. At this location

thin bedded dark-grey and black calcareous

shales and limestones occur. According to

Bristow (1976), the lithology at the type

locality consists of argillites, calcareous

argillites and sandstones which are highly

silicified and dark grey and red in colour. The

outcrop presents an old island now surrounded

by alluvium which extends for a minimum of

six kilometres in all directions. The nearest

outcrops are all of the Cayo Formation, with

the nearest outcrop of the Piñón Formation

nine kilometres to the northwest. Therefore the

designation of the Calentura outcrop as the

base of the Cayo Formation is in doubt

(Bristow, 1976).

A second outcrop of the Calentura member

described by Thalmann (1946) occurs in the

Río Paco (Pascuales area), where it overlies

Pre–Upper Cretaceous pyroclastics and

igneous intrusives. At this location, hard black

shales are found. Bristow (1976) confirms that this outcrop belongs to the basal Calentura

member of the Cayo Formation. It lies at, or

close to the base of the Cayo Formation.

Bristow further describes the presence of

breccias and tuffaceous sandstones in the Río

Paco which do not warrant the separation of

the Calentura unit as a member from the rest of

the Cayo Formation. Therefore he proposes

that the name Calentura should not further be

used.

Alvarado and Santos (1983), describe a section

of the Calentura member in the Estero Villegas

(alternatively named Estero La Mina). They

propose to keep the name Calentura as a

member of the Cayo Formation, because the

Calentura Formation can be followed as a

stratigraphical marker throughout the

Cordillera Chongón–Colonche and because it

has an age deferring from the overlying Cayo

sensu stricto member. They also note the high

amount of organic material in the fine grained

beds of the unit. Benítez (1988), investigates

the same section, but demonstrates that this

170 m thick section does not belong to the

Calentura member, but to the Cayo sensu

stricto formation, because the real contact

between the Cayo and Calentura Formation is

three kilometres more to the northeast, in La

Mina.

Santos and Alvarado (1989) mention that large

variations in thickness exist between different

sections through the Calentura unit. In the Río

Bachillero the thickness is strongly reduced

while in other areas (Estero Villegas–Paco) the

thickness is 150 metres. Benítez (1988) states

that the Calentura member does not occur in

the Río Bachillero.

Labrousse (1986) describes the Calentura

Formation at the Cerro Germania in

Guayaquil, where it covers the coarse breccia

mentioned above. He interprets the Calentura

member as distal pelagic limestones and a

proximal flysh which is commonly slumped.

Slumps indicate a paleo surface dipping to the

south.

Benítez (1990) describes the Calentura

member in the area north of Guayaquil. At this

location it has a thickness of 450 metres and it

consists of fine decimetric tobaceous turbidites

with fish remains, silicified tobaceous

claystones and micritic limestones. Coarse grained rocks like metrical white tobaceous

sandstones and conglomerates are interpreted

as turbiditic. He also observes decimetric dikes

of porphyritic rocks passing through the beds.

Because of its distinctive lithology, widespread

distribution and mappeability, Marksteiner and

Aleman (1990) suggest raising the Calentura

member to the rank of formation. They also

propose the name Chongón group, which

includes the Calentura, Cayo and Guayaquil

Formations. They still maintain the original

type locality of Thalmann (1946) for the

Calentura Formation. They state that the base

of the Calentura Formation unconformably

overlies the Piñón Formation in the Río Paco,

and that the top of the Calentura Formation is

transitional to the Cayo Formation.

Age

In the Río Paco, Thalmann (1946) found the

Cenomanian–Turonian index species

Globotruncana renzi, together with

Globigerina cretacea D’Orbigny, Guembezlina

cf. striata (Ehrenberg), G. cf. paucustriata

Albritton, G. cf. globulosa (Reuss)

Globorotalia sp., flabellammina sp., Nodosaria


6

sp., Bolivina sp. and Rheophax sp. and at least

two species of well preserved Inoceramus.

Thalmann (1946) therefore concluded that the

Calentura member must not be older than

Cenomanian and not younger than Turonian.

At the type location in Guayaquil Marks (1956

– in Alvarado and Santos, 1983) dated the

Calentura member as Upper Turonian based on

the Inoceramus species Inoceramus plicatus

d’orbigny, Inoceramus roemeri Karsten and

Inoceramus striatoconcentricus Gümbel.

Bristow (1976) does not agree with the age

proposed by Thalmann (1946). Most of the

determinations are tentative. Globotruncana

Renzi, which Thalmann (1946) regarded as a

Cenomanian–Turonian index marker, is now

known in the upper part of the Napo Formation

(Coniacian–Santonian) in the Ecuadorian

Oriente, associated with Globotruncana

globulosa. Guembezlina cf. striata is known in

the middle Napo Formation (Turonian). The

age has to be at least Coniacian. The same age

was proposed in the léxico estratigráfico of

Bristow and Hofstetter (1977).

Gamber et al. (1990 – in Marksteiner and Aleman, 1990) described the microfossil

assemblage at the Cerro Jordan in Guayaquil.

They report nanofossils Lithatrinus floralis,

Eiffelithus eximius, Marthasterites furcatus of

Coniacian age and Corollithion achysolum and

Lithastrinus planus of Turonian age, but the

Turonian nano fossils are probably reworked.

Ordóñez et al. (2006) described the fossil

assemblage of the Calentura Formation in the

Cordillera Chongón–Colonche in the Estero

Las Minas, Río Paco, Estero Limón, Estero

Guaraguau, Estero La Naranja, Estero La

Derecha, Estero Zamoreño, Río del Diablo,

Estero de Caña and the Río Grande. The

microfossil content is composed of sporadic

foraminifera, radiolaria and calcareous

nanofossils and some molluscs of the

Inoceramus species. The presence of

Archaeoglobigerina cretacea (Coniacian –

Lower Maastrichtian), Pseudotextularia nuttalli

(Coniacian–Maastrichtian), Hedbergella

holmdelensis (Coniacian – Lower

Maastrichtian), Whiteinella baltica (Upper

Cenomaniano – Lower Santonian), Whiteinella

archaeocretacea (Turonian – Coniacian),

Heterohelix moremani (Upper Albian – Lower

Santoniano), Whiteinella paradubia (Middle

Cenomanian – Upper Coniacian) and

Dicarinella imbricata (Upper Turonian –

Middle Coniacian), make it possible to infer a

Lower Coniacian to Middle Coniacian age for

the Calentura Formation.

Paleoenvironment

Ordóñez et al. (2006) report a marine reducing

environment because of the presence of early

formed pyrite (100–200 metres). In the more

calcareous part of the Calentura Formation,

more benthonic foraminifera occur represented

by Dentalina sp., Lenticulina sp., Bolivina sp.

y Cibicides sp. and the planktonic foraminifera

Heterohelix, Hedbergella, Whiteinella,

Dicarinella y Rotalipora. Because of the high

amount of heterohelícidos and hedbergélidos, a

continental platform environment is proposed

(100–200 metres). The rocks were deposited in

a quiet, warm and poorly oxygenated

environment, where a high amount organic

material was reduced by bacteria.

1.4 The Cayo Formation

Pioneering work

The first report of the Cayo Formation is found

in Olsson (1942 – in Thalmann, 1946). The

classical orthography used at that time was

Callo; but, the name Cayo, initially used only

locally, was used later on topographical maps,

and was also adapted for the 1:100 000

geological maps. The Cayo Formation was part

of the Kreideformation of Wolf (1874 – in

Bristow and Hofstetter, 1977) or the

Formación cretácica del Litoral (Wolf, 1892 –

in Bristow and Hofstetter, 1977). Wolf

recognized limestones, silicic limestone,

silicified beds, quartzite, yellow sandstone,

green sandstone and claystones in the

formation.

The type locality was defined by Olsson (1942

– in Thalmann, 1946) at the shoreline

southwest of the village of Callo (at present

times named Puerto Cayo). From its type

locality the Cayo Formation can be followed through the Cordillera Chongón–Colonche

towards the southeast in Guayaquil. North of

Puerto Cayo there are isolated outcrops of the

Cayo Formation between Jipijapa and Cerro de


7

Hojas west of Portoviejo. Thalmann (1946),

geologist of the International Ecuadorian

Petroleum Cooperation (I.E.P.C.), made an

important contribution to the stratigraphy of

the Cayo Formation. The following is cited

from his work:

The geologists of the International Ecuadorian

Petroleum Company have made a two-fold

subdivision of the Upper Cretaceous beds in

western Ecuador, that is, the coastal region

west of the Andean ranges. The lower part,

Callo Formation, is a series of compact well

bedded dark green to greenish gray tuffs

weathering pale green to ash gray, grits, and

sandstones made up of fine breccias of

volcanic material. The sediments are hard and

erosion resisting, and reach a thickness

between 10,000 and 11,000 feet. The type

locality is situated along the southern shore of

the Callo Bay, Manabí province. Excellent

exposures can be studied in the Sierras de

Chongón and Colonche, which stretch in the

form of a boomerang-shaped arch, 8

kilometres broad, from Guayaquil as far as the

sea coast north of Salango

According to Thalmann (1946) the Cayo

Formation is only 500 feet thick in the Manabí

area.

Early stratigraphical work

Sutton (1959), geologist of the I.E.P.C.,

studied the Cayo Formation in the Río

Bachillero. He was the first author to make an

entire cross-section through the formation. The

contact with the Piñón Formation was not

observed. He encounters agglomerates and

lapilli tuffs at the bottom of the Cayo

Formation, near the contact of the Piñón

Formation and states that this is an evidence

for continued volcanic activity after the

deposition of the Piñón Formation. The contact

with the overlying Guayaquil Formation is

gradational. The depositional environment of

the basal part was either terrestrial or

subaqueous since there is little rounding of the

ejecta. The later sedimentation was subaqueous

and shows an increasing amount of rounding

and a decrease in the size of the transported

material. The bedding is fairly even and little

cross-bedding is observed. He describes the

Cayo Formation as follows:

The Callo formation is a monotonous

succession of thin to massive beds of

sandstone, claystones, conglomerates, cherts,

tuffs and agglomerates. The sandstones and

conglomerates range from boulders (3 feet)

down to silt size particles. The composition of

the conglomerates which occur in the bottom

third of the section are 90 % igneous material

with the other 10 % made up of claystones,

sandstones and some cherts. The sandstones

are olive drab to brown in colour and contain

small igneous rock fragments as well as other

igneous minerals. Quartz is the most abundant

with lesser amounts of calcite, pyroxene,

plagioclase, hornblende, magnetite and some

garnets. The thickness of the beds ranges from

50 feet near the bottom of the section to only a

few inches near the top. The claystones are

very hard and well bedded and break with

conchoidal fractures while some exhibit

fissility and can be called shales. The colour of

these beds ranges from a very light cream to

olive-drab. The average thickness is two feet

and near the top they contain microfauna. The

cherts are grey to black, even to warbly

bedded, and from a few inches to two feet in

thickness. The cherts of the Callo formation differ very little from the overlying series of the

Guayaquil cherts. The tuffs are hard, silicified,

and green to bluish-gray near the bottom of the

series while at the top they are soft, white and

calcareous. The thicknesses range from 20 feet

to stringers and inch thick which separate

chert beds. The agglomerates are restricted to

the lower portion of the series and reach

approximate thickness of 400 feet. They are

characterized by a greenish colour and contain

up to cobble-size of basalt and other related

rock fragments and crystals. The matrix is

crystalline to vitric tuff.

The thickness obtained by Sutton in the Río

Bachillero was 8000 feet.

Bucaram (1966) gives a similar description of

the Cayo Formation. He distinguishes between

volcanic agglomerates at the lower part of the

formation and conglomerates in the upper part.

Agglomerates can locally attain thicknesses of

about 125 metres and are usually green to

greenish-gray and black, and composed of

small cobble-size basalt and related igneous

rock fragments and, crystals with some

associated angular lapilli ejecta.

Conglomerates in the upper part of the


8

formation are composed of up to 90 % basalt

clasts. Large boulders up to 120 centimetres in

diameter to fine grained sandstones occur.

Goossens and Rose (1973) state that the Cayo

Formation is composed of shales, siliceous

tuffs with a large amount of glauconite

(Denayer, 1968, written communication in

Goossens and Rose), chert, sandstone, and

mafic pyroclastic rocks.

In the article “The age of the Cayo Formation”,

Bristow (1976) describes the formation as

3000 metres of argillites, tuffaceous

sandstones, tuffaceous conglomerates,

greywackes, agglomerates and volcanic

breccias. The volcanic material is dominant in

the lower part of the sequence and there is

often a basal breccias at the junction with the

Piñón Formation which everywhere underlies

it. The argillites are the dominant lithology of

the succession and are often silicified. At the

top there is a gradual passage into the silicified

and chertified sediments of the overlying

Guayaquil Formation.

Feininger and Bristow (1980) demonstrate the presence of volcanic breccia of intermediate to

basic composition at the base of the Cayo

Formation. The entire lower part is dominated

by green tuffaceous sandstone and wacke.

Higher in the section, the Cayo Formation is

less volcanic, and argillite and chert are the

prevalent rock types at the top of the

formation. They state that the source of the

Cayo Formation is the Macuchi arc in the

Western Andean Cordillera. Feininger (1986)

described the Cayo Formation volcaniclastic

and sedimentary apron deposited on the sea

floor behind the Macuchi arc.

Alvarado and Santos (1983) described a

complete section of the Cayo Formation in the

Estero el Arenoso. They propose to abandon

the type locality of the Cayo Formation in

Puerto Cayo and to define a new type locality

at the Estero el Arenoso. The thickness of the

Cayo Formation is 2400 metres.

The first 70 metres of the formation consist of

porphyritic volcanic rocks, stratified, green in

colour, alternating with greenish grey calcite

rich claystones and limestones. From 70 to 450

metres the section consists mainly of hard dark

grey grauwackes, with fine intercalations of

greenish gray clay stone. From 450 to 530

metres greenish grey claystones occur, and

from 530 to 800 metres, the section is not

exposed. From 800 to 1000 metres,

grauwackes occur with thin intercalations of

clay stone, sometimes rich in calcite. From

1000 to 1180 metres grey hard silicified

claystones occur, intercalated with two levels

of grauwackes of 30 metres thick. Between

1180 and 1245 metres a conglomerate occurs

with volcanic fragments up to five centimetres

and a sandy matrix. From 1245 to 1410 metres

grauwackes occur. From 1410 to 1570 metres

claystones with thin intercalations of

grauwacke occur. From 1570 to 1930 metres

grauwackes and conglomerates alternate with

thin beds of silicified claystones. From 1930 to

2170 metres green silicified lutites occur and at

2170 metres lenticular nodules of dark-

coloured chert occur till 2400 metres. At this

point the top of the formation is in discordant

contact with the San Eduardo Formation. They

consider the inferior part as the Calentura

member, the middle part as the Cayo sensu

stricto member and the upper silicified part as

the Guayaquil member.

Santos (1983) described the Calentura

Formation as calcareous sedimentation, and the

Cayo Formation as detritic sedimentation.

During the deposition of the Cayo Formation,

“invasions” of volcanic lavas occurred, but

only in the Manabí area.

Benítez (1983) describes the Cayo Formation

as erosion of a continental volcanic arc. He

performs a petrographical study.

“Conglomerates” are lapilli tuffs, deposited in

a marine environment. He encounters samples

with 100 % volcanic fragments among which

are vitric lavas, compact or vesicular, of

basaltic or andesitic composition. The fine

material of the same rocks is hyaloclastic.

Sandstones are tuffs or tuffaceous sandstones,

deposited in turbiditic currents and show

typical Bouma sequences. Clay stones are

composed of vitric material, solidified before

the ultimate deposition and mixed with marine

sediments and microfauna. Benítez (1983)

described the cyclical deposition of the Cayo

Formation. He interprets the cycles as periods

of submarine volcanic eruptions or marine

deposits of eruptions of volcanic arcs. He also

observes a double size grading of the beds,

which requires a deep marine deposition.


9

Lapilli are deposited quickly, sand sized tuffs

fall more slowly and are transported by

turbidity currents, fine ash is sedimented

slowly, pumice floats and is dispersed by

currents.

Lebrat et al. (1987) described the Cayo

Formation as turbiditic series comprising thick

debris flows including blocks, cobbles, and

pebbles of volcanic rocks ranging from

andesite to rhyolitic welded tuffs. According to

them the volcaniclastic layers overlying ocean

floor (Piñón Formation) where issued from the

Macuchi island arc. They define the San

Lorenzo Formation in the Manabí area

consisting of a limited amount of island arc

tholeiites erupted on top of the Piñón oceanic

floor and isolated from the Macuchi arc.

Benítez (1988) investigated the Cayo

Formation in the Río Bachillero. The thickness

is 1900 metres. The Calentura member is not

present in the section. Benítez (1988)

attributed a turbiditic origin of the deposits and

recognized similar sequences as described later

in Guayaquil (Benítez, 1990). The Cayo

Formation is interpreted as prograding lobes of a marine fan. The basal part of the section is

230 metres thick and contains the thickest

sequences of the section (decametric). The

middle part is 950 metres thick and consists of

prograding sequences with a general decrease

in thickness towards the top of this part of the

section. The upper part is 160 metres thick and

contains a “slump” facies. This corresponds to

the internal part of the fan (upper fan). The

entire formation is volcanoclastic, but in the

upper 160 metres an increase in organic

material is observed, and algal fragments are

found. Benítez (1988) reports a main

paleocurrent of N260 towards the west in the

Río Bachillero. The depositional depth is

between 500–1000 m (external platform to

upper bathyal). Compared to the Guayaquil

region, the Cayo Formation is more sediment-

rich in the Río Bachillero (Benítez et al., 1996)

According to Labrousse (1986), in Guayaquil

the Cayo Formation consists at the base of

thinly bedded chocolate-coloured claystones,

alternating with 0.5–5 metre thick greenish

sandstones. The first debris flows consist of

andesitic blocks only. The Cayo Formation is

composed of four superimposed “terms”. The

basal term is a thick “debris flow” with angular

“cinerites” green or white of tuffs, green

claystones and brown sandstones. The second

term is a greenish grain flow separated from

the lower unit by an erosive surface. The third

term consists of green “cinerites” and white

tuffs. He interprets the third term as

pyroclastics reworked by sub-marine currents.

The forth term are abyssal claystones.

Labrousse (1986) interprets the Cayo

Formation as a submarine fan, situated on the

paleotallud of a volcanic arc, the Macuchi arc.

Redefinition of the type locality in

Guayaquil

Benítez (1990) suggests moving the type

locality of the Calentura, Cayo and Guayaquil

Formations to the region of Guayaquil,

because in this area, the three formations are

very well exposed. Benítez (1990) described

four types of sequences in the Cayo Formation

in the Guayaquil area:

Type 1: Decametric sequences (Ta, b) with

grain size classification conglomerates or

breccia at the base, grading into sandstones or

siltstones at the top of a sequence. The base of a sequence is generally planar, but can be

erosive too, indicating deposition in channels.

He named those sequences megaturbidites.

Type 2: Metric sequences consist of sandstone

at the base, siltstone at the top. They can be

massive at the base and laminated at the top

(terms a and b of Bouma). The base is

generally flat.

Type 3: Decimetric sequences contain micro-

stratification and convolute bedding. These

structures are not very common, decimetric

sequences consist mainly of Ta,b or maximum

Tab,c.

Type 4: Fine grained sequences. Silicic or

calcareous lutites with a microfauna of

foraminifera and radiolaria. They can be

tobaceous. They are interpreted as fine

turbidites.

He divides the Cayo (sensu stricto) Formation

in the region of Guayaquil into four members,

depending on the amount of fine grained rocks.


10

Unit C4 is 770 metre thick and consists mainly

of coarse “megaturbidites” of the following

lithologies:

- metric to decametric breccias formed

by spilitic andesitic rock fragments,

- turbiditic metric to decametric

sandstones,

- tobaceous claystones intercalated in

lower amounts,

- spilitic choritized sandy tuffs

composed of crystal clasts and glass,

- igneous dikes, metric to decimetric.

He correlated this unit with a 220 metre thick

unit of decametric megaturbidites in the Río

Bachillero. He states that the weathering of

pyroxenes shows that the rocks have a

subaereal origin.

Unit C3 is 580 metre thick and consists

predominantly of fine grained rocks, with

intercalations of metric sandstones. The base

of this unit (at the American college) consists

of 20 metres of pelites, which were dated as

Coniacian with the planktonic foraminifera

Globotruncana cf. renzi (Ordóñez). This level

can be laterally followed to Peñon del Río, the original type locality of the Calentura

Formation as defined by Thallman (1946), who

attributed a Middle Turonian to Coniacian age

with Marginotruncana cf. Renzi. However, the

assemblage should be reinterpreted as

Coniacian with Globotruncana cf. renzi

(Ordóñez). Inoceramus fragments dated as

Turonian by Marks (1956 – in Benítez, 1995)

are probably also of younger age. As this part

overlies the C4 unit, and as the underlying

Calentura Formation is of Coniacian age,

Benítez (1995) stated that the basal part of the

Cayo Formation is also of Coniacian age.

Unit C2 is 630 metre thick and consists of

decametric mega turbidites of 10–20 metre

thick. They are composed of micro breccias at

the base with a greenish colour, very hard in

fresh state, and yellowish brown when altered.

They are intercalated with decimetre thick

silicic tobaceous claystones and metric

lithofeldspatic sandstones. The green colour is

caused by chloritization. Benítez (1996) is the

first author to describe this unit

microscopically. The grauwackes are

lithofeldspatic with a smectitic or vitric matrix.

The volcanic fragments are andesitic basalts,

vesicular to fluidal dacites, dacitic perlites,

vesicular lavas with pumpellyite, and

fragments of molluscs.

Unit C1 is 280 metre thick and consists of

decimetre thick fine grained beds. The beds are

composed of tobaceous claystones and fine

decimetric turbidites. They are intercalated

with decimetric to metric sandstones and mega

turbidites. Even near the contact with the

Guayaquil Formation, mega turbidites occur.

To describe the vertical variation through the

Cayo Formation, Benítez (1990) differentiates

between two types of sequences: A–sequences

present a decrease in thickness and grain size.

They are mainly channels and are deposited

proximal to the source area. They occur mainly

in the C2 to C5 members of the Cayo

Formation. E–sequences: are coarsening

upwards and increase in thickness. They

characterize deposits of a more distal fan.

Benítez (1990) sees an increase in A: E ratio

towards the top of the Cayo Formation, which

he interprets as more proximal facies towards

the top of the formation. He interprets the

Cayo Formation to be deposited in the middle

part of a submarine fan.

Marksteiner and Aleman (1990) describe

thinning and fining cycles in the Cayo

Formation in the Guayaquil region with

scoured bases interpreted as submarine

channels. Marksteiner and Aleman note that

some shales may represent ash-fall tuffs and

other tuffaceous sediments with abundant

silica cement are derived from devitrification

of volcanic glass. Sandstones are cemented

with zeolites, chlorite and calcite.

Agglomerates are common with hyaloclastic

breccias present in the lower part of the

section. Basaltic and basaltic andesitic lavas

occur but are sometimes difficult to distinguish

from sills. Some of the volcanoclastic

sandstones and conglomerates as well as the

lava flows show indications of greenschist

metamorphism. The composition of the

sandstones (tuffs) varies from volcanic lithic

rich to feldspar rich. Some of them contain

abundant pumiceous fragments (vitric rich).

The volcanic fragments vary from vitric to

lathwork and the plagioclase varies from

intermediate to high anorthite contents and can

be zoned.


11

Gamber et al. (1990) interpret the formation to

be deposited subaqueously by sediment gravity

processes similar to those described elsewhere.

The sediments were derived from the erosion

or contemporaneous volcanic activity of an

immature arc building subaerially or

subaqueously. Deposition took place from

turbidity currents and debris flows in the deep

marine to slope environment. Several thinning

and fining upward cycles and erosional

scouring suggest the existence of deeply

incised channels, and the documentation of

discrete thickening and coarsening cycles

could be indicative of a middle fan

environment. However, this facies might

represent a response to volcanic activity and

rate of sediment input rather than depositional

processes.

Wallrabe-Adams (1990) states that the contact

between the Piñón and Cayo Formation is

mostly unconformable. Most of the Cayo

Formation consists of a variety of

volcaniclastic rocks (breccias, conglomerates,

fine grained tuffs) with rare sedimentary

intercalations. Subordinate effusive volcanic

rocks are restricted to the lower part, consisting of submarine lavas (partly pillowed) and sub-

volcanics. In contrast to the Piñón Formation,

vesicular textures are common, possibly

indicating emplacement at a lesser water depth.

Near Puerto Cayo the formation is dominated

by volcanoclastic rocks with some intercalated

lavas and sedimentary rocks. Near Guayaquil

the abundance of sediments increases upward

within the volcaniclastic sequences. The

uppermost unit in Guayaquil, the Guayaquil

unit consists of cherts. Most of the volcanic

rocks of the Cayo Formation are layers of

massive lavas of a few metres thick, but some

pillow lavas are present. In addition, sub-

volcanic rocks occur as large volcanic stocks

or discordant dykes. Pillow lavas are filled

with a mixture of celadonite (and/or saponite),

calcite and quartz. Massive lavas and pillow

lavas are porphyritic with only rare fluidal

textures. Sub-volcanic rocks are medium or

seldom coarse grained and holocrystalline. The

main constituents are plagioclase (andesine–

labradorite), augite and some hypersthene. No

amphibole or olivine is present. Wallrabe-

Adams only refers to the Guayaquil Formation

as sedimentary. Wallrabe-Adams (1990)

interprets the Cayo Formation as

volcaniclastic-epiclastic beds, partly build up

from the erosion of the Macuchi island arc.

Jaillard et al. (1995) interpret the Cayo

Formation as a 2000 metre thick succession of

fining-upwards, coarse grained volcaniclastic

sandstones and conglomerates, including a

spectrum from high- to low-density turbidites

with shaly intercalations. The Coarse grained

sedimentation contrast markedly with the

underlying fine grained deposits and indicate

that an important geodynamic change occurred

by Late Coniacian – Early Santonian time.

Reynaud et al. (1999) describe the Cayo

Formation as 2000 metres of turbiditic shales,

greywackes and conglomerates.

Luzieux et al. (2006) defined the Cayo

Formation as a 2000–3000 metre thick series

of debris flows and turbidites, which display a

general upwards thinning trend. Coarse debris

flows at the base of the formation may be

synchronous with volcanic activity, but there is

no clear evidence for arc activity until the end

of the Cayo Formation. Part of the sequence

could be derived from the erosion of a non-

active arc.

Luzieux (2007) described the Cayo Formation,

as typically repeated thinning and fining

upward sequences of light olive green-

coloured, volcano-derived debris flows and

silicified turbidites. The coarse, less silicified

basal beds, with bed thicknesses of

approximately one to five metres, often show

concentric, onion-type weathering structures.

Most of these beds show a bimodal grain-size

distribution, although upward grading (T) and

laminar bedding (Tb) can sometimes be

observed at the top of the beds. The upper part

of the sequence is characterized by silicified,

decimetre to centimetre scale thick turbidites,

which regularly show T to T, Bouma–

sequences, although T structures can be

occasionally observed. The wavy aspect

sometimes observed between beds is due to

“boudinaging” caused by the irregular

diagenetic compaction of the siliceous

sediments.

Luzieux (2007) estimated the maximal

thickness of the Cayo Formation at Guayaquil

to be approximately 2400m. The formation

thickness decreases gradually towards the

northwest, and the formation disappears in the


12

area of Portoviejo–Manta. The Cayo

Formation is generally more silicified in the

Piñón Block than elsewhere and contains only

a few pumice clasts, which are commonly

observed in more northern exposures. The with

the Calentura Formation contact cannot be

observed, but similar regional dips observed in

both formations indicate either a conformable

to para-conformable nature. The lower part of

the series is mainly composed of angular to

sub-angular volcanic clasts, embedded into a

matrix of smaller volcanic fragments of ortho-

and clinopyroxene, hornblende, plagioclase,

oxides and volcanic glass.

Luziex (2007) stated that the Cayo Formation

becomes finer grained towards its upper part,

which is accompanied by a gradual increase in

the fraction of bioclasts, which become

dominant at the top of the formation. Sponge

spicules and radiolarian skeletons are mainly

responsible for siliceous cementation in the

upper part of the Cayo Formation. Both

benthonic and planktonic foraminifera are also

present. The planktonic foraminifera have

abnormally thin tests, which are often broken

and squeezed due to sediment compaction. The abundance of millimetre to centimetre wide

burrow structures towards the top of the

formation is indicative of significant

bioturbation activity. The overall fining

upward trend observed in grain-size and

bedding thickness probably reflects the

progressive erosion of the volcanic arc source

area. However, deepening of the basin due to

general subsidence (associated with

submergence of the sourcing arc), may also

have contributed to the fining upward trend.

The smaller, second–order fining upward

cycles are interpreted to be the result of lateral

migration of mid- and lower fan depocenters in

a deep-sea environment.

Age

The age of the Cayo Formation determined by

Thalmann (1946) in the Guayaquil region is

Upper Cretaceous, as confirmed by other

authors in other regions (Sutton, 1959;

Bucaram, 1966; Feininger, 1986) and more

specifically Senonian (Turonian–

Maastrichtian), as is confirmed by Bristow

(1976). A further specification could not be

made, because of the lack of good

foraminiferal assemblages. According to

Marksteiner and Aleman (1990) the Cayo

Formation might be of Late Turonian to Early

Maastrichtian age. Gamber et al. (1990)

identified the presence of dinocysts of Late

Santonian to Maastrichtian age in the Cayo

Formation, although these beds could belong

to the upper Calentura Formation.

In more recent biostratigraphical work, the age

is refined. Ordóñez et al (2006) described the

microfossil assemblage of the Cayo Formation

in the Cordillera Chongón–Colonche. The

microfauna is composed of foraminifera,

calcareous nanofossils, dinoflagellata,

radiolaria and palinomorphs. A Middle

Campanian age was determined, with

radiolaria as guiding fossils Pseudoaulophacus

lenticulatus (Middle Campanian), Vitorfus

morini (Campanian) and Amphipyndax tylotus

(Middle Campanian – Maastrichtian). Gomez

and Minchala (2003) dated the Middle Cayo

Formation (right above the Lower Cayo

Formation) in the Río Derecha as Middle

Campanian. Luzieux et al. (2006) dated the

middle and the upper part of the formation at

two locations. The following associations were

observed:. 1.- Radotruncana subspinosa, Rugotruncana subcircumnodifer,

Globotruncana aegyptiaca, Globotruncana

linneiana (M. Caron); and. 2.- Abathomphalus

intermedius, Globotruncanita stuarti,

Radotruncana subspinosa, Globotruncana

linneiana, Globotruncanita species (Caron – in

Luzieux et al., 2006). These associations

correlate with the Middle–Late Campanian.

Paleoenvironment

As indicated above, various authors interpret

the deposits of the Cayo Formation as formed

on the talud of an active or inactive volcanic

arc. Although previous authors suggested that

the source of the Cayo Formation was the

Maccuchi Formation, which crops out in the

western Cordillera, it is now known that the

Maccuchi arc is of much younger Paleocene to

Eocene age (Vallejo et al., 2006). Ordóñez et

al. (2006) interpred the paleoenvironment

bathyal, based on assemblages of benthic

foraminifera, radiolaria and dinoflagellata.

Jaya et al. (2006) interpreted the rocks of the

Cayo Formation as back-arc deposits because

of the caesium anomalies they encounter in the

rocks. Luzieux (2007) states that the source

area must have been in the east, but as


13

sediment deposition can occur both parallel as

orthogonal to the arc axis, it is difficult to

know if it was deposited in the arc area or in a

back-arc environment. From the study of

heavy mineral assemblages Luzieux (2007)

states that all Cretaceous formations are devoid

of continent derived heavy minerals indicating

that the Cayo Formation was deposited in a

intra oceanic volcanic arc. Van Melle et al.

(2008) attributed the deposits of the Cayo

Formation as formed from the erosion

associated to the growth of a nearby arc and

interpret the Cayo Formation as a back-arc

deposit.

1.6 The Guayaquil Formation

Thalmann (1946) distinguished the Cayo

Formation from the overlying Guayaquil

Formation and correlated the Guayaquil and

Santa Elena Formation, which occurs towards

the south in the Santa Elena Peninsula. The

type locality is defined by Thalmann (1946)

and Sheppard (1946) in the old neighbourhood of Ferroviaires a San Pedro in Guayaquil, but

the old type section is removed by

urbanization.

The contact with the overlying part, the

Guayaquil formation (Guayaquil chert series),

is gradational, as shown where the coarse

clastic and tuffaceous sediments of the Callo

formation pass upwards into cherts with tuffs.

The Guayaquil formation is composed

essentially of silicified tuffs with thin-bedded

buff to black cherts and thin partings of hard

dark grey tuffaceous shales, reaching about

1500 feet in thickness in the Sierras of

Chongón and Colonche, and, under the name

of “Santa Elena cherts” in the Santa Elena

Peninsula, attaining a thickness of 2000 feet.

The type locality of the Guayaquil formation is

opposite the bridge over the Estero Salado at

the western exit of the town of Guayaquil.

…

It is found in the Sierra de Chongón and

Colonche from Guayaquil as far west as the

headwaters of the Río de la Pampa (about 80

kilometres west of Guayaquil). The highly

fractured, hard and brittle, buff, light gray and

white siliceous tuffs with veins or stringers of

chalcedony and black or gray “augen”–

growth chert, known as the “Santa Elena

cherts” in the Santa Elena Peninsula-, are an

age-equivalent of the Guayaquil formation.

Locally they include thin sandstone beds made

up of volcanic material and greenish or dark

greyish shales. The maximum thickness is 2000

feet.

…

In western Ecuador, Manabí province, the

Guayaquil formation reaches a thickness of

4500 feet and is composed mainly of thin chert

beds with seams of tuffaceous shales,

siliciceous ash, and tuffs. Good outcrops can

be observed in the Río Mariano, in the Río Viti

and along the borders f the Jama–Cuaque

Mountains.

Thalmann (1946) attributed the paucity of

microfossils largely to the great volcanic

activity which prevailed during the end of the

upper Cretaceous time in western Ecuador.

The high degree of silicification of the water

laid tuffs (percolation of siliceous solutions)

was undoubtly a greatly destructive ecologic

factor in the biofacies of the sediments.

Nevertheless Thalmann (1946) believed that a

Maastrichtian age can be attributed to the

Formation.

Bristow (1976) stated that since much of the

silicification is secondary (Sinclair and Berkey,

1924 – in Bristow, 1976), it is presumed that

the level of silicification is not always the same

and it is thought that the Cayo-Guayaquil

contact is not everywhere of the same age.

This is supported by the fauna. For this reason

Bristow proposes to relegate the Guayaquil

Formation to member status at the top of the

Cayo Formation. In the léxico estrátigrafico of

Bristow and Hofstetter (1977), the Guayaquil

Formation is considered as the upper member

of the Cayo Formation.

Sigal (1969 – in Bristow, 1976) recorded a

Maastrichtian fauna in the Soledad–Buena

vista area at 20 kilometre SSE of Puerto Cayo.

The lithology of silicified argillites pertains to

the Guayaquil member and Sigal has suggested

that the planktonic foraminifera (small

globigerinas seen in thin section) may be as

young as Danian.

Marksteiner and Aleman (1990) demonstrated

the important volcanic contribution to the

rocks of the Guayaquil Formation. Benítez


14

(1988) proposed to raise the Guayaquil

member to formation.

Benítez (1990) proposed a new type section of

the Guayaquil Formation along the Via

Perimetral in Guayaquil. Benítez distinguished

two members:

- Lower member: alternation of black

pelites of centimetre to decimetre

thickness which are silicified to

nodules of silex, and subordinary

brown, tuff-like siltstones. The

thickness is 85 metres in Bellavista.

The benthic foraminifera Bolivinoides

draco draco indicate a Late

Maastrichtian age (M. Ordóñez in

Benítez, 1990). The Cretaceous–

Tertiary boundary occurs 35 metres

from the top of the lower member.

- Upper member: occurs in the

Hormigonera quarry in Guayaquil. At

the base it is composed of tuffs with

calcite cement in centimetre to metre

beds. Higher in the section, pelites

occur. The member is 240 metres thick.

The depositional setting is interpreted as

bathyal (200–2000 metres) by Unocal (1987–

in Benítez, 1995).

Luzieux (2007) finds rounded zircons in the

Guayaquil Formation which indicate a

continental attribution, meaning that the Piñón

block was approaching, or was already

accreted to the South American margin.


15

References

Only the references which were not given in

the List of References of the main text, are

given here.

Allibon, J., Monjoie, P., Lapierre, H., Jaillard,

E., Bussy, F., Bosch, D., Senebier, F., 2008.

The contribution of the young Cretaceous

Caribbean Oceanic Plateau to the genesis of

Late Cretaceous arc magmatism in the

Cordillera Occidental of Ecuador. Journal of

South American Earth Sciences, 26: 355-368.

Alvarado G., Santos M., 1983. El Miembro

Calentura y la Formción Cayo. Tercer Congreso

de Geología Minas y Petróleo. 13 p.

Bristow, C., 1976. The age of the Cayo

Formation, Ecuador. Newsletters on

Stratigraphy, 4: 169-173.

Bristow, C., Hoffstetter, R., 1977. Lexique

stratigraphique International. Volumen V.

Amerique Latine (Sous La Direccion de R

Hoffstetter.). Facicule 5 a 2. Ecuador.

Deuxième Edition par C.R. Bristow et R

Hoffstetter avec la collaboration de T.

Feininger et M.T. Hall.

Bucaram, R., 1966. Reporte Geológico de la

Costa Ecuatoriana. Ministerio de Industrias y

Comercio, Asesoria Tecnica de Petroleos,

Quito, Ecuador. 13p.

Feininger, T., 1986. Allochthonous terranes in

the Andes of Ecuador and northwestern Peru.

Canadian Journal of Earth Sciences, 24: 266-

278.

Feininger, T., 1986. Allochthonous terranes in the Andes of Ecuador and northwestern Peru. Canadian Journal of Earth Science, 24, 266-278.

Gamber, J.H., Barker, G.W., Stein, J.A., Carney, J.L., Geen, A.F., Krebs, A.F., Salomon, R.A., White, R.J., 1990. Biostratigraphic report on Coastal Ecuador. Unpublished report of Amoco, Guayaquil, Ecuador. 65 p.

Goossens, P.J., Rose, W.I., 1973. Chemical

composition and age determination of tholeiitic rocks in the basic Cretaceous Complex,

Ecuador. Geological Society of America

Bulletin, 84: 1043–1052.

Goossens, P.J., Rose, W.I., Flores, D., 1977.

Geochemistry of tholeiites of the Basic

Igneous Complex of Northwestern South

America. Geological Society of America

Bulletin, 88: 1711–1720.

Haase, K.M., Stroncik, N.A., Hékinian, R. &

Stoffers, P. 2005. Nb-depleted andesites from

the Pacific-Antarctic Rise as analogs for early

continental crust. Geology, 33, 921-924.

Santos, M. N., Alvarado, G.S., 1989. Informe

geológico. Bordes de la subcuenca Manabí.

Unpublished report of CEPE, Ecuador. 44p.

Sutton, E.H., 1959. Geology of the Colonche

hills, Julio Moreno and Los Pocas area,

progresso basin, guayas province – Ecuador.

Unpublished report of California Ecuador

Petroleum Company. Guayaquil, Ecuador. 71

p.

Lebrat, M., Mégard, F., Juteau, T., Calle, J.,

1985. Pre-orogenic volcanic assemblages and structure in the Western Cordillera of Ecuador

between 1°40’S and 2°20’S. Geologische

Rundschau, 74 (2): 343-350.


16

Appendix 2 – Field and sample locations

17

This appendix is included at the end of this pdf

All GPS coordinates are in the coordinate Prov. S. Am. 1956. All data fall in the UPM zone 17s.

APPENDIX 2 – FIELD AND SAMPLE LOCATIONS

Appendix 2 – Field and sample locations

18

Appendix 3 – Methodology for mineralogical characterization

19

3.1 Sample preparation for X-ray

diffraction

Micronizing of the sample

- Take representative amounts of sample (50-

100 g). Crush the sample by hand in a

porcelain mortar. Use shock impact for

grinding, avoid shearing. Pass the entire

sample through a 500 µm sieve.

- Pre-hydrate the sample in an equilibration

chamber of 52% relative humidity for at least

16 hours to achieve complete hydration of all

zeolites, to minimize weighing errors. This

equilibration chamber can be easily

constructed with a standard laboratory glass

dessicator and an oversaturated

Mg(NO3)2.6H2O solution.

- Weigh 2.7 grams of sample; add 0.3 g (10%)

of ZnO internal standard. Note down the exact

weights.

- Micronize the samples in a McCrone

Micronizing mill using 5 ml of methanol as

grinding agent and a grinding time of 7.5

minutes.

- After micronizing, recuperate the sample in

porcelain cups. Cover the cups with plastic foil, because recovery of powder from the

porcelain is difficult. Wash with methanol to

recuperate as much as possible of the sample.

- Dry for one-two days under a fume hood

(methanol is toxic). Do not use any extra

heating to speed up drying (oven).

Preparation for X-ray diffraction

- Dried samples are gently disaggregated in an

agate mortar and passed through a 250µm

sieve, to ensure good mixing of sample and

ZnO standard.

- To ensure that samples are ground up to < 10

µm, the size required for X-ray quantification,

the grain size is checked by (wet) laser

diffraction analysis.

- +/- 0.5 g of sample is needed for the X-ray

analysis. Side-loading with frosted glass is

recommended to fill sample holders, to prevent

preferential orientation of fibrous zeolites and

clay minerals. Sample holders are gently

tapped while filling, to ensure good packing of

the grains. Alternatively, back loading is used.

- Samples (in sample holders) are pre-hydrated

at 52% relative humidity for at least 16 hours

to prevent peak-shifts caused by dehydration.

If swelling occurred (surface is not flat

anymore), sample holders are refilled.

X-ray measurement

The following parameters were used for X-ray

measurement:

Philips PW1830 diffractometer with

Bragg/Brentano θ – 2 θ setup, CuK radiation,

45kV and 30 mA, graphite monochromator,

receiving slit width: 1 mm; divergence slit

width: 1 mm. Antiscatter slit width: 0.1 mm,

stepscan or continuous scan.

- Scan range: 3-70° 2θ.

- Stepsize: 0.02° 2θ.

- Time/step: at least 2 seconds, longer than 5

seconds is not recommended, because of

possible dehydration of the zeolites during the

measurement.

APPENDIX 3 – METHODOLOGY FOR

MINERALOGICAL CHARACTERIZATION


20

3.2 Methodology for cation

exchange capacity measurements

of zeolitic rocks

Method

Method of Vassilieva & Machiels modified

from Kitsopoulos (1999).

Principle

The AMAS method involves the saturation of

the zeolite with ammonium (NH4+) ions that

replace exchangeable cations. The number of

NH4+ ions retained by the zeolite, is a measure

of the CEC. There are four steps: 1) NH4OAc

saturation and cations exchange; 2)

measurements of cations in solution by AAS;

3) release of NH4 and generation of NH4

solution; 4) measurements of NH4+ in solution

by Nessler.

Standard Reference Material

Th 002 CEC Ca Mg K Na

meq/1

00g

d.w.

160 40 10 82 28

Reagents

1. Ammonium acetate NH4Ac, 2M. Dissolve

154 g of C2H7NO2, p.a. in 1000ml DW

2. Sodium Chloride 10% acidified with HCl to

0.005M. Dissolve 100g of NaCl, p.a. in

some DW, add 0.5ml HCl conc. and make

up to 1000 ml with DW.

3. Ca, Mg, K, Na Standard stock solutions

1000 ppm for AAS.

4. NH4 Standard stock solution 1000 ppm:

Dissolve exactly 1.4878 oven dried (105°C)

NH4Cl p.a. in some DW. Make up to 500

ml.

5. NH4 Standard solution 10 ppm: Prepare

fresh! Take 1ml of NH4 1000ppm and make

up to 100ml with DW. 6. Nessler reagents: Dissolve 2.5g Potassium

Iodide (KI p.a.) in 10 ml DW. Place on the

magnetic stirrer. Add saturated solution of

HgCl2 (dissolve about 3.7 g HgCl2 p.a. in

50ml DW under strong stirring, let it stay

overnight, decant the clear solution) until

the precipitation occurs. Add 25ml of 30%

NaOH solution (30 g NaOH p.a. in 100ml).

Make up to 200 ml with DW and mix

thoroughly. The solution has to be filtered

with 0.45µm Milli-pore filters before use.

HgCl2 (mercury(II)chloride): R28: Very toxic

if if swallowed, R34: Causes burns; R50/53:

Very toxic to aquatic organisms, may cause

long-term adverse effects in the aquatic

environment; 48/24/25: Toxic: danger of

serious damage to health by prolonged

exposure in contact with skin and if swallowed;

S45: In case of accident or if you feel unwell,

seekmedical advice immediately (show the

label where possible); S60 : This material

and/or its container must be disposed of as

hazardous waste; S61: Avoid release to the

environment. Refer to special

instructions/safety data sheets. S36/37/39:

Wear suitable protective clothing gloves, and

eye/face protection; S(01/02): (Keep locked up

and out of reach of children); Hazard symbol

T+ : Very toxic

7. K, Na-tartrate 20%. Dissolve 20g of K, Na-

tartrate p.a. in 100 ml DW.

Apparatus

1. Analytical balance

2. Centrifuge tubes, Nalgene, 80ml

3. Horizontal shaker

4. Funnels

5. Volumetric flasks: 1 L, 500 ml, 200ml, 100

ml, 25 ml

6. ICP tubes 15ml 7. Automatic pipettes: 1-5 ml, 200-1000 µl,

10, 15, 20ml volumetric pipettes

8. Cuvettes for spectrophotometer

9. Spectrophotometer

1. Sample preparation

1. Samples are ground by hand in a mortar

and passed through a 125 µm sieve.

2. Place sample in centrifuge tube, add

deionised water and centrifuge 10


21

minutes at 4000 rpm and decanted to

remove soluble salts.

3. This procedure is repeated twice

4. Samples are dried < 40°.

5. Samples are prehydrated prior to

weighing for at least 16h in a desiccator

with a saturated solution of

MgNO3.6H2O.

2. NH4+ -saturation and HN4

+ -cations

exchange

1. Weigh 0,50g of sample in a clean centrifuge

tube. Include one reference sample and one

blank (it will serve as a matrix for standards

and as a blank for colorimetric

determination of NH4+, so you MUST

handle the blank the same way you do your

samples). Take 2 replicates for each sample!

It is important because the procedure is

quite long and complicated, the chance of

mistake is sufficient.

2. Add 20 ml of NH4OAc 2M.

3. Mount the tubes on the horizontal shaker

and let it shake for 24 hours

4. Centrifuge 10 minutes at 4000 rpm

5. Decant the supernatant carefully in 100ml

flask.

6. Repeat the procedure (extraction with 20ml

NH4OAc) twice with the shaking time 5

days (day 5 and day 10). Collect the

supernatant in 100ml flask (one for each

sample). 7. “Wash” the residue 2 times with 10 ml

NH4OAc and collect clear supernatant in the

100ml flask. Make up to 100ml. Close,

shake to mix.

This solution (A) is to be measured by AAS for

Ca, Mg, K, Na (exchangeable cations).

3. Release of saturating NH4+

1. “Wash” the residue at least 3 times with

50ml of DW. Do not loose any residue

while poring away the rinse water.

2. Add 20ml NaCl solution, shake thoroughly

by hand, centrifuge 10 minutes at 4000 10

minutes and collect the clear supernatant in

200ml flask.

3. Repeat the procedure at least 6 times. Make

up to 200ml with DW. Close the flask,

shake to mix. Take about 15ml of the

solution and filter it with 0.45µm filter in

15ml ICP tube.

This solution (B) is to be measured for NH4+

by VIS-spectrophotometry after Nessler’s

reaction

.

4. NH4+ measurements

Note: Switch ON the spectrophotometer and

adapt the wavelength at 400nm at least 2 hour

before the measurements.

1. Take 25ml flasks. Add some (±10ml) DW

in each flask.

2. Add 500µl of the blank (NaCl solution) in

each flask for the standards and 500µl of

the NH4+ released solution (B) for each

sample.

3. Add HN4+ 10 ppm in volumes according to

the table below.

4. Add 1ml of K,Na-tartrate.

5. Add 1ml of Nessler’s reagents

6. Make up to 25 ml with DW. Close and mix

thoroughly.

The concentration of the standards are shown

in the table:

blank st1 St2 st3 st4

Ml stock 10

ppm 0 0.5 1 1.5 2

Concentrati

on, ppm 0 0.2 0.4 0.6 0.8

st5 st6 st7 st8 st9 st10

2.5 3.0 3.5 4.0 4.5 5.0

1.0 1.2 1.4 1.6 1.8 2.0

7. Let react for 10 minutes.

8. Measure the absorbance at 400nm. Zero is

blank-to-blank.

Calculate the results using linear regression in

Excel.

Disposal of chemical waste

As HgCl2 is very toxic, all solutions containing

this product should be disposed off via

chemical waste containers category 5.


22

References:

[1] Pabalan, R.T., Bertetti, F.P., “Cation-

Exchange Properties of Natural Zeolites,”

In: Bish, D.L., Ming, D.W., Editors,

Natural Zeolites: Occurence, Properties,

Applications, Mineralogical Society of

America, Washington D.C., 2003, pp. 453-

517.

[2] Kitsopoulos, P.K., “Cation-exchange

capacity (CEC) of zeolitic volcaniclastic

materials: applicability of the ammonium

acetate saturation (AMAS) method,” Clays

and Clay Minerals 47, Vol. 6, 1999, pp.

688-696.

[3] Leonard, R.H., 1961. Quantitative Range of

Nessler’s Reaction with ammonia. Clinical

chemistry 9 (4): 417-421.


23

3.3 Staining of feldspars & zeolites

Method

Modified from

http://www.scn.org/~bh162/staining_feldspars.

pdf

CHEMICALS

Hydrofluoric Acid = concentrated (52 percent),

which is how it comes from the bottle.

Sodium Cobaltinitrite = saturated solution; 1g

in 4 ml H2O (D253)

Barium Chloride = saturated solution; start

with 5 grams in 25 ml of distilled, deionized

water; add more Barium Chloride and stir until

some will not dissolve. Allow some of the

undissolved residue to remain in the bottom of

the jar, but do not stir or shake immediately

before using. (D42)

Amaranth = saturated solution; use about 1

grams of the purple-red amaranth powder in 10

ml of distilled, deionized water. (D9)

Potassium chloride => saturated solution

THIN SECTION STAINING PROCEDURE (standard)

Caution: Use the required chemicals in a fume

hood and do not get any on your skin.

For sedimentary petrology, half-stained

sections are desirables; therefore you must

mask the half of the section that is to be left

unstained. Wrap one-inch wide masking tape

gently around one end of the slide, overlapping

the loose ends on the back. Seal tightly the

edge of the tape crossing the center of the slide

but do not push hard on the rest of the tape or

you may have trouble removing the tape later.

If the thin section may be greasy (from

fingerprints and such), wipe it gently with

acetone or denatured alcohol, being careful not

to touch the tape.

Etch the face of the thin section with

concentrated hydrofluoric acid for 1 to 3

seconds. Use extreme caution in handling HF:

wear a rubber apron, goggles, and rubber

gloves (test your gloves in water to be sure

they have no leaks). Do the etching in a fume

hood that is turned on. You will need a plastic

eyedropper, a shallow plastic dish, and a

plastic beaker full of water. Do not put HF in a

glass container: the acid dissolves glass. Hold

the thin section, rock side up, over the shallow

dish. Take a dropper full of HF and, beginning

in the center of the thin section and moving

towards the sides, cover the unmasked half of

the sample with acid, letting excess acid run

off into the dish. Put the dropper down in a

safe spot and then dip the thin section several

times in the beaker of water to rinse it. Move to

the sink, and rinse off any remaining acid with

running water. Gently blow the thin section

dry.

Immerse the unmasked end of the thin section

in a saturated solution of sodium cobalinitrite

for 15 seconds. Rinse off the excess

cobaltinitrite in tap water and dry gently but

thoroughly with compressed air (you may also

warm the section in a warm oven to dry it

completely).

Immerse the unmasked end of the section in a

saturated solution of barium chloride for 15

seconds. Dip in water to rinse off excess

solution, and blow dry.

Hold the unmasked end of the section in a saturated solution of amaranth for 5 seconds.

Dip twice in standing water to rinse off some

of the excess amaranth (do not overrinse or the

red dye will be removed from the plagioclase)

and blow dry.

Gently remove masking tape, taking care not to

peel the rock off the slide.

Results: K-feldspar and K-zeolites will be

stained yellow, plagioclase and Ca-zeolites

will be stained purple. Na-zeolites and albites

are not stained. A small amount of Ca in Na-

zeolites or albite will give it a light pink

colour. The intensity of the colour can be

related to the Ca-content


24

THIN SECTION STAINING

PROCEDURE (staining albite and Na-zeolites)

Method

Modified from Bailey and Stevens (1960)

Procedure

Etch the sample with HF (see standard

procedure)

Immerse the unmasked end of the section in a

saturated solution of potassium chloride for 15

seconds. Dip in water to rinse off excess solution, and blow dry.

Immerse the unmasked end of the thin section

in a saturated solution of sodium cobalinitrite

for 15 seconds. Rinse off the excess

cobaltinitrite in tap water and dry gently but

thoroughly with compressed air (you may also

warm the section in a warm oven to dry it

completely).

Results: K will replace Na in zeolites and in

etched albite. The K will react with sodium

cobalinitrite and stain the zeolites and albite

yellow.

Reference: Bailey, E.H., Stevens, R.E., 1960. Selective

staining of K-feldspar and plagioclase on rock

slabs and thin sections. The American

Mineralogist, 45, 1020-1025.


25

3.4 Digestion of silicate rock

samples: LiBO2 fusion in graphite

crucible for AAS and ICP-MS

analysis

Method

Method of Vassilieva (modified from: Solution

technique for analysis of silicates. N.H.

Suhr&C.O. Ingamells. Anal.Chemistry Vol.,

38 N° 6. May 1966 (p. 730-734)

Principle

Fusion with LiBO2 followed by rapid

dissolution in 0.42M nitric acid brings all

constituents in solution.

Standard Reference Material

Ask lab responsible for suitable standard and

include it in the batch.

Reagents

1. Lithium metaborate, LiBO2, 100% non

fused, CAS 13453-69-5. (Flux Nr 100A.

from Spectroflux)

2. Nitric acid (HNO3), 0.42M. Dilute 30 ml

of concentrated nitric acid to 1 L with

distilled water. 3. Cesium chloride Lanthanum chloride

AAS buffer solution (10% La, 1% Cs)

4. For dilutions: Nitric acid (HNO3),

0.42M. Dilute 30 ml of concentrated

nitric acid to 1 L with distilled water (for

ICP-MS use Milli-Q).

Apparatus

1. 5ml tubes

2. Graphite crucible (Carbon of America

002380-000, Crucible YU40)

3. Analytical balance

4. Muffle furnace

5. Magnetic stirrer

6. 100 ml polypropylene beaker

7. 50 ml PP bottles of ICP tubes

Procedure

1. Put ON muffle furnace 2 hours before

you start.

2. Weigh 100.0 mg of the sample in a

5ml tube. Include at least one blank

and 4 reference samples in each batch.

3. Add 500 mg LiBO2 to the sample.

Close the tube and shake it to mix.

4. Transfer the mixture in a graphite

crucible.

5. Place the graphite crucible in the

muffle furnace and heat at 1000°C for

10 minutes.

6. Place a polypropylene beaker with 50

ml HNO3 0.42M in a magnetic stirrer

and let it stir.

7. Take out the graphite crucible and

swirl the content gently (to ensure melt

is homogeneous and that complete

solution is achieved) and quickly pour

out in the beaker with HNO3.

8. Stir the mixture until everything is

dissolved and replace the solution in a

50 ml plastic bottle.

9. This solution should be measured with

AAS or ICP-OES (1/10!!!) after

dilution.

10. For AAS: Take 20ml of the solution

and add 1 ml of Cs-La AAS buffer

solution.

Note: Always use thermo gloves and a pincer

while handling hot graphite crucibles. Be

careful and stay calm!

In the case of using only ICP-OES or ICP-

MS do not add Cs-La solution!


26

Appendix 4 – mineralogical characterization of the Late Cretaceous deposits

27

4.1 Structures used in the Rietveld refinement.

Table 1 Structures used in the Rietveld refinement.

Possible ranges of cell parameters for zeolites are from Passaglia and Sheppard (2001). The column

reference refers to the references below.

APPENDIX 4 – MINERALOGICAL

CHARACTERIZATION OF THE LATE CRETACEOUS

DEPOSITS

Appendix 4 - Characterization of the Late Cretaceous deposits of Coastal Ecuador

28

Name a (Ǻ) b (Ǻ) c (Ǻ) α (°) β (°) γ (°) reference space group chemistry

adularia 8.55-8.729 12.8-13.058 7.118-

7.262 115.48-117 8 C 1 2/m 1

K4Al4Si12O32

albite (An0) 8.12-8.15 12.7-12.81 7.13-7.20 94-95 116.4-117 87.0-

88.2 4 C-1

NaAlSi3O8

analcime 13.66-

13.73 9 I a -3 d

Na(AlSi2O6)(H2O)

andesine (An52) 8.16-8.19 12.85-12.88 7.07-7.12 93.4-

93.7 116.0-116.4

89.5-

90.0 16 C -1

Na0.622Ca0.368Al1.29Si2.71O8

apophyllite 8,979 15,83 28 P 4/m n c KCa4(Si8O20)(OH)(H2O)8

augite 9.597-

9.791 8.762-8.940

5.217-

5.323 106-107.6 22 C 1 2/c 1

(Mg0.72Fe0.25Al0.02Ti0.01)

(Ca0.78Na0.02Mg0.03Fe0.16Mn0.01)

(Si1.95Al0.05O6)

barrerite 13.59-

13.64 18.18-18.20

17.79-

17.84 29 A m m a

Na9.9K3.46Ca3.52 Al15.9Si56.1O144(H2O)44.68

bytownite (An

85) 8.17-8.195 12.86-12.91

14.17-

14.22

93.1-

93.6 115.5-116.3

90.2-

91.4 7 P -1

Ca0.85 Na0.14 Al1.94 Si2.06 O8

calcite 4.95-5.0 16.9-17.1 33 R -3 c R Ca(CO3)

celadonite 5,23 9,05 10,15 100,58 34 C 1 2/m 1 KFe1.5Mg0.5Si4O10(OH)2

chabazite 13.69-

13.86

14.18-

15.42 23 R -3 m R

(Ca0.85K0.66)Mg0.66(Al3.31Si8.69O24)(H2O)13.22

chlorite 5.25-5.5 9.15-9.45 14.1-14.6 95.0-97.0 19 C 1 2 1 Mg2.5Fe1.65Al1.5Si2.2Al1.8O10(OH)8

cristobalilte 27 P 41 21 2 SiO2

diopside 9.653-

9.849 8.842-9.020

5.255-

5.308 105-107 15 C 1 2/c 1

(Ca0.96Na0.04)(Mg0.86Al0.07Fe0.06)(Si1.89Al0.11O6)

dolomite 4.8-4.88 15.90-

16.42 26 f c b a

CaMg(CO3)2

epistilbite 9.08-9.10 17.74-17.80 10.20-

10.24

124.55-

124.68 2 C 1 2 1

Na0.95Ca2.85(Al6Si18O48)(H2O)14

erionite 13.19-

13.34

15.04-

15.22 12 P 63/m m c

K2Ca2.44Mg0.52(Al7.908Si28.092O72)(H2O)21.6

goethite 466,894 1.016.243 306,247 13 P b n m FeO(OH)

Appendix 4 – mineralogical characterization of the Late Cretaceous deposits

29

Name a (Ǻ) b (Ǻ) c (Ǻ) α (°) β (°) γ (°) reference space group chemistry

hematite 5.01-5.07 13.7-13.83 3 R -3 c H Fe2O3

hornblende 9.73-9.94 17.9-18.2 5.25-5.37 104 17 C 1 2/m 1 (K.3 Na.6) (Ca1.7 Mg0.3) (Mg3 Fe Fe0.5 Al0.3Ti0.2)

Al1.6 Si6.4 O22.5(OH)1.5

Heu-type 17.62-

17.74 17.81-18.05 7.39-7.53

116.13-

116.90 5 C 1 2/m 1 (Na1.32 K1.28 Ca1.72 Mg0.52)(Al6.77 Si29.23

O72).26.84(H2O)

labradorite

(An65) 8.17-8.182

12.86-

12.883 7.08-7.12

93.3-

93.7 115.9-116.3

90.2-

90.9 20 P 1 1 21/a

Ca7.902 Na1.73 (Al5.5 Si0.5 O18)

laumontite 14.69-

14.89 13.05-13.17 7.53-7.61 110-113 30 C 1 2/m 1

Ca4(Al8Si16O48) (H2O)ue

magnetite 83,958 104.5-106 32 F d -3 m Z Fe3O4

mordenite 18.05-

18.25 20.35-20.53 7.49-7.55 18 C m c 21

K2.99Ca1.85Na1.06Al7.89Si40.15O96.28H2O

oligoclase

(An16) 8.15-8.165 12.81-12.84 7.13-7.16

93.8-

94.3 116.3-117

88.0-

89.0 25 C-1

(Na0.84Ca0.16) Al1.16Si2.84O8

pumpeleyite 8,83 5,9 19,17 97,12 11 A 1 2/m 1 Ca8Mg1.4 Fe.6 Al10 Si12O44 (OH)10(H2O)2

pyrite 54,179 6 P a -3 FeS2

quartz 4.9-4.935 5.38-5.45 21 P 32 2 1 SiO2

stellerite 13.57-

13.63 18.16-18.27

17.82-

17.87 24 F m m m

Ca4(Al8.32Si27.68)O72 (H2O)35.36

stilbite 18.18-

18.33 18.18-18.33

17.71-

17.84 90.20-91.15 10 C 1 2/m 1

Na1.76 Ca4.00 (Al10.29Si25.71O72)(H2O)29.4

thomsonite 13.00-

13.18 13.04-13.16

13.09-

13.24 1 P n c n

Na1.08 Ca1.84 Sr.08 (Al5 Si5 O20) (H2O)6

tridymite 4.95-5.00 8.62-8.65 8.31-8.35 93-95 14 C 1 c 1 SiO2


30

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31

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stellerite, Ca (Al8 Si28) O72 . 28 (H2 O). Crystal Research and Technology, 21(8): 1029-1034.

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Kristallphysik, Kristallchemie, 133: 43-65.

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displacement parameters in carbonates: Calcite and aragonite Ca C O3, dolomite Ca Mg (C O3)2, and

magnesite Mg C O3. acta Crystallographica B, 54: 515-523.

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Variation of framework geometry with temperature. Journal of Applied Physics, 57: 1045-1049

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redefinition of the apophyllite group. II. crystal structure. The American Mineralogist, 63: 196-202.

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Crystallographica, 11: 191-195.

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32

(34) Zhukhlistov, A.P., Zvyagin, B.B., Lazarenko, E.K., Pavlishin, V.I., 1977. Refinement of the

crystal structure of ferrous seladonite. Kristallografiya, 22: 498-504.

33

4.2 XRD quantifications

4.2.1 Río Guaraguao section (samples are ordered from the base to the top of the section)

Sample name qua cal lau alb oli and lab pla adu aug mag pum pre Hor NQ chl remarks

04LM095Q 6 17 19 36 27 1 30 x

09LM072Q 6 0 0 5 23 0 16 38 0 28 2 0 0 0 21 x Opal-CT

09LM071Q 14 0 37 37 0 0 0 0 0 3 0 0 0 0 9

09LM076K X

09LM078Q 21 8 31 22 0 0 0 0 0 4 1 4 0 0 9

09LM079Q 75 0 0 1 4 0 0 4 3 0 0 0 0 0 17

09LM081Q 23 2 4 3 31 0 0 31 3 7 1 0 0 0 25

09LM082K X ?

09LM083Q 21 0 0 2 10 4 25 39 2 8 0 0 0 0 28

06LM001Q 96 5 0 0 0 0 0 0 0 0 0 0 0 0 0

06LM011Q 50 46 0 0 0 0 0 0 0 0 0 0 0 0 4

06LM012Q 38 4 0 0 16 0 0 16 0 3 1 0 0 0 44

06LM013Q 10 0 34 0 26 0 0 26 0 3 1 0 0 0 27

06Lm014Q 57 9 0 0 17 0 0 17 0 0 0 0 0 0 17

06Lm015Q 51 39 0 0 0 0 0 2 0 0 0 0 0 0 8

06LM005Q 77 0 0 13 0 0 0 0 0 1 0 0 0 0 9 x

06LM006Q 14 12 57 5 0 0 0 0 0 2 0 0 0 0 10

06LM007Q 15 11 59 5 0 0 0 0 0 2 0 0 0 0 8 x

06LM009Q 2 2 53 0 0 0 0 0 0 8 0 0 0 0 35

06LM008Q 66 16 3 0 0 0 0 2 0 2 0 0 0 0 11 x

06LM003Q 37 0 4 36 0 0 0 0 0 7 1 4 10 0 0

06LM004Q 28 0 7 31 0 0 0 0 0 8 1 7 0 0 18 x epistilbite?

06Lm016Q 37 0 8 0 41 0 0 41 0 4 1 0 0 0 10 clast

09LM085Q 18 0 20 0 29 0 0 29 0 9 2 4 0 0 20

06LM096Q 1 0 0 36 0 0 0 0 0 3 0 58 0 0 2 clast

06Lm097Q 36 0 3 0 0 46 0 46 0 6 0 0 0 0 9

06LM098G 49 0 7 4 20 0 0 20 0 2 0 0 0 0 17

06LM098R 62 0 0 0 0 0 0 9 0 2 0 0 0 0 27


34

Sample name qua cal heu mor lau sti ste ana alb oli and lab byt pla adu aug mag pum cri try NQ cel chl remarks

06LM099Q 61 1 0 2 0 0 0 0 0 5 0 0 0 5 0 2 0 0 0 0 28

06LM100Q 32 0 0 2 0 0 0 0 0 21 0 0 0 21 0 3 0 0 0 0 42 missing?

06LM101Q 14 0 7 59 0 0 0 0 0 0 0 0 0 3 0 2 0 0 0 0 15

09LM086Q 21 0 0 0 21 0 0 0 5 19 0 0 0 19 0 15 0 6 0 0 12 missing?

06LM102Q 34 0 0 0 35 0 0 0 26 0 0 0 0 0 0 0 0 0 0 0 1 hor: 2%

09LM088Q 29 0 0 0 51 0 0 0 17 0 0 0 0 0 0 4 0 0 0 0 0

09LM089Q 27 0 46 0 0 0 0 0 6 5 0 0 0 5 4 3 0 0 0 0 10

06LM103Q 50 0 6 3 0 0 0 0 0 0 0 0 0 4 0 2 0 0 0 0 34

09LM001Q 36 0 0 0 29 0 0 0 30 0 0 0 0 0 0 0 2 0 0 0 3

09LM002Q 32 1 0 0 0 0 0 0 21 0 0 0 0 0 0 0 0 0 0 0 46

09LM003Q 31 0 29 3 0 13 10 0 11 0 0 0 0 0 0 0 0 0 0 0 3 x

09LM004Q X x x x

09LM005Q 35 0 0 0 39 3 0 0 16 0 0 0 0 0 0 0 1 0 0 0 7

09LM006K 35 0 0 0 5 0 0 0 21 0 0 0 0 0 0 0 0 0 0 0 39

09LM007K 35 0 0 0 21 0 0 0 21 0 0 0 0 0 0 0 0 0 0 0 23

09LM008Q 33 0 0 0 24 0 0 0 32 0 0 0 0 0 0 0 1 0 0 0 9

09LM009Q 33 0 0 0 20 0 0 0 37 0 0 0 0 0 0 0 0 0 0 0 10

09LM010Q 21 0 0 0 38 0 0 0 21 0 0 0 0 0 0 5 0 0 0 0 16 ?

09LM011Q 17 1 0 0 11 0 0 0 36 0 0 0 0 0 0 11 0 0 0 0 23 ? x

06LM104Q 25 0 0 0 12 0 0 0 53 0 0 0 0 0 0 0 0 0 0 0 10

06LM105Q 46 6 0 0 0 0 0 0 0 17 0 8 0 25 0 2 1 0 0 0 35 14 clast

06LM106-2 12 0 20 3 2 4 0 0 0 17 0 13 0 30 0 9 0 0 0 0 28 8 x

09LM012Q 50 0 0 0 29 0 0 0 8 0 0 0 0 0 0 0 0 0 0 0 12

09LM013Q 25 0 4 40 0 0 0 0 6 0 0 0 0 10 2 3 1 0 0 0 10 ?

09LM014Q 21 0 0 38 0 0 0 0 2 5 6 9 0 20 2 2 0 0 0 0 15 ?

09LM015Q 24 1 30 0 0 8 7 0 0 15 0 0 0 15 0 3 0 0 0 0 12 x

09LM016Q 19 0 10 34 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 33 x x

09LM017Q 47 0 0 0 28 0 0 0 11 0 0 0 0 0 0 0 0 0 0 0 15

09LM018Q 29 9 0 0 36 3 0 0 11 0 0 0 0 0 0 2 1 0 0 0 9 x x

35

Sample name qua cal heu mor lau sti ste ana alb oli and lab byt pla adu aug mag pum cri try NQ cel chl remarks

09LM019Q 31 7 21 15 0 0 0 0 4 0 0 3 0 3 0 3 0 0 0 0 16 x x

09LM020Q 31 4 0 0 35 0 0 0 8 0 0 0 0 0 0 2 1 0 0 0 19 ?

09LM021Q 25 0 1 21 0 0 0 0 2 0 0 22 0 22 0 4 0 0 0 0 26 x

09LM022Q 69 0 0 0 5 8 0 0 0 16 0 0 0 16 0 1 0 0 0 0 0 ste?

09LM023Q 25 0 7 21 0 0 0 0 4 0 0 19 0 19 0 5 0 0 0 0 20 x x

09LM024Q 26 0 13 0 9 0 0 0 3 18 8 0 0 26 2 8 0 0 0 0 13 x

09LM025Q 24 0 4 31 0 0 0 0 4 0 0 15 0 15 0 4 0 0 0 0 19 x

09LM026Q 28 0 7 40 0 0 0 0 0 3 0 9 0 12 0 2 0 0 0 0 11 x

09LM027Q 15 0 0 0 37 0 0 0 27 0 0 0 0 0 0 7 0 0 0 0 13 x

09LM028Q 23 0 8 13 5 0 0 0 3 8 0 0 13 20 0 6 2 0 0 0 19 x

06LM108Q 23 0 12 26 0 0 0 0 0 0 0 29 0 29 0 10 0 0 0 0 1 x x

09LM029Q 29 0 0 0 37 0 0 0 20 0 0 0 0 0 0 0 2 0 0 0 11 ? x

09LM030Q 24 0 3 39 0 0 0 0 0 10 0 0 0 10 0 0 0 0 0 0 24 x x

09LM031Q 44 32 0 0 0 0 0 0 0 0 0 0 0 3 0 0 0 0 0 0 21

06LM109Q 27 3 0 0 43 0 0 0 18 0 0 0 0 0 0 3 0 0 0 0 5 x

06LM110Q 33 0 0 0 47 0 0 0 18 0 0 0 0 0 0 0 0 0 0 0 2 x

09LM032Q 17 0 0 0 49 0 0 0 21 0 0 0 0 0 0 0 1 0 0 0 12 ? x

09LM033Q 24 0 0 0 31 0 0 0 29 0 0 0 0 0 0 0 2 0 0 0 14 ? x

06Lm112Q 8 0 5 0 0 0 0 0 0 0 16 0 0 16 0 11 0 0 0 0 59

06LM113Q 15 0 0 0 16 11 0 0 26 0 0 0 0 0 0 7 1 0 0 0 23 x

06LM114Q 12 0 34 0 0 0 0 0 7 16 0 0 0 16 0 8 0 0 0 0 24 x

09LM035Q 16 0 0 0 28 0 0 0 23 0 0 0 0 0 0 6 1 0 0 0 25 x

09LM036Q 14 0 32 3 4 0 0 0 0 16 0 0 0 16 0 8 1 0 0 0 23 x x

06LM115Q 19 0 17 20 0 0 0 0 0 13 0 6 0 19 0 7 0 0 0 0 18 x x

09LM038Q 19 0 14 28 0 0 0 0 0 8 0 4 0 12 0 6 0 0 0 0 20 ? x

06LM116Q 21 0 5 40 0 0 0 0 0 11 0 4 0 15 0 3 0 0 0 0 17 x x

09LM039Q 22 0 32 0 0 10 8 0 0 13 0 0 0 13 0 3 0 0 0 0 12 x

09LM040Q 41 20 5 7 0 0 0 0 0 11 0 0 0 11 0 0 0 0 0 0 16 x

09LM041Q 39 8 28 7 0 0 0 0 0 3 0 0 0 3 0 0 0 0 0 0 16 x

09LM042Q 15 0 18 21 0 0 0 0 2 6 0 9 0 15 0 4 1 0 0 0 24 x

06LM118b 23 19 31 5 0 0 0 0 0 3 0 3 0 6 0 2 0 0 0 0 17 3


36

sample name qua cal heu mor lau sti ste ana alb oli and lab byt pla adu aug mag pum cri try NQ cel chl remarks

06Lm118t 4 0 30 4 0 0 0 0 0 12 0 15 0 27 0 8 0 0 0 0 32 6 x

06LM119Q 12 0 37 15 0 0 0 0 0 0 0 0 0 9 0 3 0 0 0 0 31 5 x

09LM043Q 27 0 23 26 0 0 0 0 0 12 0 0 0 12 0 0 0 0 0 0 12 x

06LM120Q 27 8 14 0 0 0 0 0 0 21 0 0 0 21 0 6 0 0 0 0 25 x

06LM121Q 4 0 47 0 0 0 0 0 0 0 0 0 0 13 0 7 0 0 0 0 28 x x

06LM122Q 16 0 44 11 0 0 0 0 0 0 0 0 0 10 0 5 0 0 0 0 14 x

06LM178Q 6 0 53 0 0 0 0 0 0 10 0 0 0 10 0 8 0 0 0 0 23

06LM179Q 44 0 14 20 0 0 0 0 0 0 0 0 0 7 0 0 0 0 0 0 15

06LM123Q 37 0 29 16 0 0 0 0 0 2 0 0 0 2 0 3 0 0 0 0 13

06LM176Q 3 1 59 0 0 0 0 0 0 16 0 0 0 16 0 8 0 0 0 0 14 x

06LM177Ge 51 0 0 0 8 0 0 0 24 0 0 0 0 0 0 0 1 0 0 0 17 missing?

06LM177Gr 58 0 0 0 16 0 0 0 20 0 0 0 0 0 0 0 1 0 0 0 5 missing?

06LM124Q 24 0 7 0 19 0 0 0 13 23 0 0 0 23 0 3 1 0 0 0 11

06LM073Q 37 0 6 43 0 0 0 0 0 0 0 0 0 8 0 0 0 0 0 0 6

06LM074Q 2 0 55 3 0 0 0 0 0 0 0 11 0 11 0 6 0 0 0 0 23 ? Sti?

06LM075Q 50 2 18 10 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 21 ? Sti?

06LM077Q 20 0 12 47 0 0 0 0 0 0 0 0 0 10 0 0 0 0 0 0 17 5

06Lm078Q 40 0 5 46 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 8

06LM079Q 8 1 9 0 0 0 0 8 0 20 0 0 0 20 0 10 0 0 0 0 44 ?

06Lm080Q 26 3 13 0 0 0 0 5 0 9 4 0 0 13 0 0 0 0 0 0 12 apo:

28%

06LM081Q 29 0 0 58 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 16 3

06Lm082Q 36 4 0 0 0 55 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5

06LM085Q 9 0 44 0 0 7 0 0 0 24 0 8 0 32 0 4 0 0 0 0 5 x x

06Lm086Q 12 0 15 36 0 0 0 0 0 0 0 0 0 9 0 3 0 0 0 0 25 x

06LM087Q 32 13 0 0 42 0 0 0 5 0 0 0 0 0 0 0 0 0 0 0 8

06LM088Q 36 18 26 4 0 7 0 0 0 0 0 0 0 7 0 0 0 0 0 0 2

09LM051K 37 20 14 13 0 0 0 0 2 0 0 1 0 1 0 1 1 0 0 0 11

09LM052Q 8 4 12 16 0 0 0 0 2 9 0 21 11 40 0 5 0 0 0 0 13 ?

09LM053Q 11 2 19 21 0 0 0 0 2 7 0 7 8 22 0 4 1 0 0 0 19 x x

09LM054Q 16 0 12 29 0 0 0 0 4 0 0 6 9 16 0 4 0 0 0 0 19 x x

09LM055Q 11 1 13 20 0 0 0 0 2 5 0 15 5 25 0 6 0 0 0 0 20 x

37


09LM056Q 16 7 13 44 0 0 0 0 2 0 0 0 3 3 0 3 0 0 0 0 12 x

09LM057Q 11 5 12 30 0 0 0 0 0 6 0 13 0 19 0 5 0 0 0 0 17

09LM058C 19 15 8 39 0 0 0 0 0 2 0 2 0 5 0 1 0 0 0 0 12 ?

09LM058F 40 12 13 12 0 0 0 0 0 3 0 2 0 6 0 2 1 0 0 0 16

09LM059K 31 7 20 9 0 0 0 0 0 0 0 5 0 5 0 2 1 0 0 0 27

09LM060Q 9 2 14 20 0 0 0 0 4 0 0 24 0 24 0 5 1 0 0 0 20 x

06LM089Q 17 0 16 28 0 3 0 0 0 0 0 0 0 19 0 0 0 0 0 0 17 x x

09LM061Q 16 0 8 27 0 0 0 0 0 10 0 20 0 29 0 4 0 0 0 0 16 ? ?

09LM062Q 13 0 9 21 0 0 0 0 0 9 0 13 15 38 0 5 0 0 0 0 14

09LM063Q 5 0 12 49 0 0 0 0 0 2 0 4 0 5 0 3 0 0 0 0 26

09LM069Q 41 0 2 42 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 15

06Lm090Q 13 0 10 58 0 0 0 0 0 0 0 4 0 4 0 0 0 0 0 0 15 ?

06LM091Q 33 0 3 51 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 12

09LM066Q 20 0 7 52 0 0 0 0 0 1 0 0 2 3 0 2 0 0 0 0 15

06LM093Q 37 1 11 37 0 0 0 0 0 0 0 0 0 5 0 1 0 0 0 0 6

06LM125Q 37 28 8 5 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 0 20

06LM126Q 24 0 12 49 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 15

06LM127F 32 2 44 0 0 0 0 0 0 0 0 0 0 3 0 3 0 0 0 0 16

06LM127G 19 7 14 25 0 0 0 0 0 0 0 0 0 14 0 3 0 0 0 0 18

06LM128Q 14 9 18 4 0 0 0 0 0 0 0 0 0 20 0 5 1 0 0 0 29 x

06LM129Q 9 4 13 0 11 0 0 0 12 19 0 0 0 19 3 6 1 0 0 0 20 x x

06LM131Q 7 2 13 0 0 0 0 0 0 31 0 0 0 31 0 9 2 0 0 0 36 x

06LM132Q 10 4 25 14 0 0 0 0 0 0 0 0 0 20 0 6 2 0 0 0 19 x

06LM133Q 8 0 37 17 0 0 0 0 0 0 0 0 0 4 0 4 0 0 0 0 30

06LM135Q 35 10 19 0 0 0 0 0 5 10 0 0 0 10 0 2 0 0 0 0 19

06LM136Q 1 7 38 4 1 0 0 0 0 0 0 0 0 37 0 8 0 0 0 0 3

06Lm138Q 27 18 18 2 0 0 0 0 0 0 0 0 0 12 0 4 0 0 0 0 19

06LM138B 25 17 14 3 0 0 0 0 0 0 0 0 0 12 0 4 0 0 0 0 25

06LM145Q 2 0 22 0 0 0 0 0 0 18 0 19 0 37 0 9 2 0 0 0 28 x

06Lm146Q 12 3 11 2 6 0 0 0 0 39 0 0 0 39 11 7 2 0 0 0 8 x

06LM148Q 3 0 44 3 0 0 0 0 0 12 0 15 0 27 0 8 1 0 0 0 14 x


38


06LM149Q 14 2 0 0 21 0 0 0 12 21 0 0 0 21 0 12 0 0 0 0 19 x

06LM150Q 4 1 37 3 2 0 0 0 4 10 0 18 0 28 0 9 1 0 0 0 9 x

06LM151Q 1 0 23 0 0 0 0 0 0 0 0 0 0 24 0 8 1 0 0 0 43

06LM153Q 4 4 0 0 23 0 0 0 0 0 0 0 0 36 0 7 0 0 0 0 27 pum?

06LM154Q 1 0 24 1 8 0 0 0 0 30 0 0 0 30 0 12 1 0 0 0 22 x

06LM155Q 5 4 32 0 0 0 0 0 0 0 0 0 0 29 0 11 1 0 0 0 19

06LM157Q 0 0 36 2 0 0 0 0 0 35 0 0 0 35 0 16 1 0 0 0 9

06LM158Q 4 0 45 2 0 0 0 0 0 27 0 0 0 27 0 9 1 0 0 0 13 x

06LM159Q 10 2 33 3 0 0 0 0 0 31 0 0 0 31 0 9 0 0 0 0 12

06LM160Q 24 5 54 2 0 0 0 0 0 0 0 0 0 12 0 0 3 0 0 0 7 ?

06LM161Q 17 6 64 0 0 0 0 0 0 0 0 0 0 5 0 0 1 0 0 0 8

06LM162Q 3 1 25 0 0 0 0 10 0 22 0 0 0 22 0 14 0 0 0 0 25 x

06LM163Q 8 11 47 0 0 0 0 0 0 11 0 0 0 11 0 3 0 0 0 0 20

06LM164Q 11 0 40 0 0 0 0 0 0 17 0 0 0 17 0 0 0 0 0 0 31

06LM165Q 4 0 40 2 0 0 0 0 0 31 0 0 0 31 0 8 0 0 0 0 15

06LM166Q 0 2 4 0 0 0 0 28 0 0 0 0 0 5 0 22 1 0 0 0 38

06LM167Q 0 3 34 0 0 0 0 0 0 17 0 0 0 17 0 13 0 0 0 0 33 x

06LM168Q 0 4 26 0 0 0 0 0 0 27 0 0 0 27 0 16 0 0 0 0 27

06LM168R 0 2 59 0 0 0 0 0 0 15 0 0 0 15 0 5 0 0 0 0 19

06LM169Q 6 0 67 0 0 0 0 0 0 7 0 0 0 7 0 3 0 0 0 0 15

06LM170Q 14 3 55 0 0 0 0 0 0 16 0 0 0 16 0 0 0 0 0 0 12

06LM171Q 0 3 34 0 5 0 0 1 0 0 0 0 0 22 0 14 0 0 0 0 20 x

06LM172Q 2 0 64 0 0 0 0 0 0 9 0 0 0 9 0 4 0 0 0 0 21

06LM175Q 48 0 36 0 0 0 0 0 0 8 0 0 0 8 0 2 0 0 0 0 6

06LM180T 0 5 25 0 0 0 0 0 0 17 0 18 0 35 0 14 0 0 0 0 21

06LM180T2 0 5 25 0 0 0 0 0 0 13 9 24 0 47 0 13 0 0 0 0 10

06LM181Q 30 6 33 0 0 0 0 0 0 15 0 0 0 15 0 3 0 0 0 0 14

06LM182Q 5 4 19 0 0 0 0 0 0 31 0 0 0 31 0 7 0 0 0 0 34

06LM184Q 44 0 30 0 0 0 0 0 0 4 0 0 0 4 0 0 0 0 0 0 22

06LM186Q 57 2 17 0 0 0 0 0 0 8 0 0 0 8 0 3 0 0 0 0 12

06LM187Q 6 2 11 0 0 0 0 0 0 11 17 13 0 40 4 11 0 0 0 0 30 5? x mor?

39


06LM188Q 5 2 12 0 0 0 0 0 0 17 0 18 0 35 6 11 0 0 0 0 30 x

06LM190b 28 6 34 0 0 0 0 0 0 10 0 0 0 10 0 2 0 0 0 0 19

06LM192Q 41 0 16 0 0 0 0 0 0 9 4 17 0 30 0 0 0 0 0 0 14

06LM193bl 27 0 49 4 0 0 0 0 0 13 0 0 0 13 0 0 0 0 0 0 7

06LM193Br 6 4 48 2 0 0 0 0 0 17 0 4 0 21 0 6 0 0 0 0 14

06LM194Q 5 6 21 0 0 0 0 0 0 13 21 0 0 34 0 9 0 0 0 0 24 ?

06LM196Q 52 0 39 0 0 0 0 0 0 5 0 0 0 5 0 0 0 0 0 0 4

06LM198Q 1 6 24 0 0 0 0 12 0 0 0 0 0 1 0 10 0 0 0 0 46

06LM199Q 60 0 15 3 0 0 0 0 0 9 0 0 0 9 0 3 0 0 0 0 10

06LM201Q 3 0 27 2 0 0 0 0 0 18 0 16 0 34 6 10 1 0 0 0 15

06LM202Q 44 0 36 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 0 18

06LM072Q 10 4 25 0 0 0 0 0 0 0 22 0 0 22 0 6 1 0 0 0 32

06LM067Q 7 3 38 0 0 0 0 0 0 8 8 0 0 16 0 5 0 0 0 0 38 7 x

06LM068Q 13 2 26 0 0 0 0 0 0 0 0 0 0 28 2 5 0 0 0 1 24 4 x

06LM069Q 50 6 31 0 0 0 0 0 0 0 0 0 0 3 0 0 0 0 0 0 10

06LM066Q 44 6 30 0 0 0 0 0 0 0 0 0 0 3 0 0 0 0 0 0 17

06LM070Q 1 7 38 0 0 0 0 0 0 0 0 0 0 27 0 7 1 0 0 0 18

06LM071Q 2 14 28 0 0 0 0 0 0 4 0 0 0 4 0 0 0 0 0 0 53

06LM065Q 2 14 29 0 0 0 0 0 0 4 0 0 0 4 0 0 0 0 0 0 51

06LM063Q 29 0 46 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 21

06LM064Q 31 0 54 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 14

06LM061Q 9 2 42 0 0 0 0 0 0 12 0 0 0 12 0 6 1 0 0 0 29 x

06LM060Q 4 1 34 0 0 0 0 0 0 0 0 0 0 16 0 5 1 0 0 0 38

06LM058Q 43 0 31 0 0 0 0 0 0 10 0 0 0 10 2 2 0 0 0 1 11 6?

06LM057Q 4 0 50 0 0 0 0 0 0 0 0 0 0 18 0 7 1 0 0 0 27 6?

06LM054Q 2 0 48 0 0 0 0 0 0 0 0 0 0 14 0 4 1 0 0 0 31

06LM051Q 74 0 9 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 0 15

06LM047Q 46 21 16 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 13


40


06LM043Q 4 4 51 0 0 0 0 0 0 0 0 0 0 11 0 6 1 0 0 0 24

06LM040Q 62 0 29 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 5

06LM036Q 53 0 42 0 0 0 0 0 0 0 0 0 0 3 0 0 0 0 0 0 1

06LM035Q 10 0 38 4 0 0 0 0 0 0 0 0 0 20 6 4 1 0 3 0 16 6

06LM034Q 6 0 53 0 0 0 0 0 0 0 0 0 0 17 5 4 1 0 0 2 11

06LM033Q 67 0 10 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 21

06LM031Q 5 0 43 0 0 0 0 0 0 0 15 0 0 15 6 5 1 0 0 2 21

06LM026Q 65 0 15 0 0 0 0 0 0 0 0 0 0 2 0 2 0 0 1 0 15

06LM024Q 65 0 10 0 0 0 0 0 0 0 0 0 0 0 0 2 1 0 2 0 19

06LM022Q 18 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 43 25 14

06LM021Q 4 0 2 0 0 0 0 0 0 0 20 0 0 20 0 3 2 0 4 0 66

06LM020Q 24 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 37 23 17

06LM019Q 92 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 8

06LM017W 96 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4

06LM017Z 100 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

NQ = not quantified

41

4.2.2 Guayaquil (samples are ordered from the base to the top of the section)

Sample name qua cal heu-

type mor lau ana alb oli and lab byt pla

K-

fsp aug chl mon cel mag act others NQ Remarks

06LM204 6 0 0 0 0 0 14 17 0 0 0 31 2 24 0 0 0 0 0 0 38

06LM205 28 0 0 0 0 0 14 31 0 0 0 45 0 0 0 0 0 0 11 0 27

06LM207 30 0 0 0 0 0 3 10 15 3 0 31 0 0 0 0 0 0 10 0 39

06LM263 47 0 0 0 0 0 41 0 0 0 0 41 0 0 0 0 0 0 0 0 11 ankerite?

06LM264 34 0 0 0 0 0 8 34 0 0 0 41 0 0 0 0 0 0 5 0 25

06LM265 48 0 0 0 0 0 40 11 0 0 0 51 1 0 0 0 0 0 0 0 0

06LM215 X 0 epidote

06LM217 33 0 0 0 0 0 15 29 0 0 0 44 3 0 0 0 0 0 0 0 20

06LM219 28 9 0 0 0 0 19 21 0 0 0 40 0 0 0 0 0 0 0 3 21 barite

06LM221 30 0 0 0 0 0 11 36 0 0 0 47 1 4 0 0 0 0 3 0 18 ankerite?

06LM222 29 0 0 0 0 0 6 16 0 0 0 21 0 0 0 0 0 0 9 0 49

06LM223 29 0 0 0 0 0 23 16 0 0 0 39 0 0 0 0 0 0 1 0 32

06LM224 26 0 0 0 0 0 12 8 0 0 0 20 0 0 0 0 0 0 22 0 54

06LM225 47 0 0 0 0 0 47 0 0 0 0 47 0 0 0 0 0 0 0 0 6

06LM226 62 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 7 31 goethite

06LM255 51 6 0 0 0 0 11 0 0 0 0 11 0 0 0 0 0 2 0 0 31

06LM256 62 2 0 0 0 0 22 0 0 0 0 22 0 0 0 0 0 0 0 0 14

06LM260 51 2 0 0 0 0 22 0 0 0 0 22 0 0 0 0 0 2 0 0 24

06LM261 41 11 0 0 0 0 8 0 0 0 0 8 0 0 0 0 0 0 0 0 40

06Lm282 33 60 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 7

04LM014Q 57 32 0 0 0 0 0 4 0 0 0 4 0 0 0 0 0 0 0 0 6

06LM242 15 8 0 0 0 0 6 15 0 0 0 21 0 6 0 0 0 0 0 0 50

06LM243 2 7 0 0 0 0 22 19 0 0 0 42 0 15 0 0 0 1 0 10 23 prenite

06LM229 23 5 0 0 0 0 23 13 0 0 0 35 0 0 0 0 0 0 0 0 37

06LM232 17 5 0 0 0 0 52 0 0 0 0 52 0 0 0 0 0 0 0 0 26

06LM233 21 5 0 0 0 0 15 28 0 0 0 43 0 0 0 0 0 0 0 0 30

06LM236GROEN 45 1 0 0 0 0 34 7 0 0 0 40 0 0 0 0 0 0 0 2 12 cristobalite


42


type Mor lau ana alb oli and lab byt pla

K-


06LM237 24 6 0 0 0 0 15 22 0 0 0 37 0 0 0 0 0 0 0 0 33

06LM238 26 6 0 0 0 0 42 0 0 0 0 42 0 0 0 0 0 0 0 0 25

06LM241 14 45 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 40

06LM267 37 0 0 0 0 0 33 0 0 0 0 33 11 0 0 0 0 0 0 0 19

06LM268 30 0 0 0 0 0 5 23 0 0 0 28 11 2 0 0 0 1 0 0 28

04LM118Q 47 8 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 45

06LM276 24 5 0 0 0 0 19 13 0 0 0 33 5 4 0 0 0 0 0 0 30

06LM277 55 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 41

06LM279 30 0 0 0 17 0 35 0 0 0 0 35 0 0 0 0 0 1 0 0 17

06LM280 62 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 38

06LM281 88 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 12

06LM283 6 9 0 0 0 0 0 0 10 6 0 15 0 26 0 0 0 1 0 0 43

04LM084Q 50 13 0 0 0 0 18 16 0 0 0 34 3 0 0 0 0 0 0 0 1

04LM128Q 2 0 11 5 0 0 0 0 9 0 0 9 4 0 0 0 0 0 0 0 69

05RS051Q 77 0 0 0 0 0 0 4 0 0 0 4 13 0 0 0 0 0 0 4 2 Barite

05RS052Q 82 0 0 0 0 0 17 0 0 0 0 17 0 0 0 0 0 0 0 0 2

05RS053Q 25 0 0 0 0 0 56 0 0 0 0 56 0 0 0 0 0 0 0 0 19

05RS054Q 47 36 0 0 0 0 0 5 0 0 0 5 10 0 0 0 0 0 0 0 2

05RS055Q 38 0 0 0 0 0 50 0 0 0 0 50 0 0 0 0 0 0 0 0 12

05RS057Q 74 0 0 0 0 0 0 5 0 0 0 5 8 0 0 0 0 0 0 0 13

05RS058Q 84 1 0 0 0 0 0 13 0 0 0 13 0 0 0 0 0 0 0 0 3

05RS059Q 45 1 0 0 13 0 16 23 0 0 0 39 0 0 0 0 0 0 0 0 2

05RS062Q 65 21 0 0 2 0 10 0 0 0 0 10 4 0 0 0 0 0 0 0 3

43


type Mor lau ana alb oli and lab byt pla

K-


04LM085Q 34 0 0 0 15 0 36 0 0 0 0 36 2 0 0 0 0 0 0 0 13

06LM304Q 31 12 0 0 0 0 6 21 0 0 0 28 22 0 0 0 0 0 0 0 8

06LM306Q 20 4 0 0 0 0 0 0 0 31 0 31 3 0 0 0 0 1 0 0 41

04LM086Q 20 0 0 0 0 0 5 34 0 0 0 39 0 0 0 0 0 0 0 0 42

04LM130Q 45 0 0 0 0 0 11 27 0 0 0 37 0 0 0 0 0 0 0 0 17

06LM286 26 1 0 0 0 0 8 25 0 0 0 33 16 2 0 0 0 1 0 0 21

06LM290 23 0 0 0 13 0 24 31 0 0 0 55 0 0 0 0 0 1 0 0 8

06LM291Q 29 0 0 0 19 0 40 0 0 0 0 40 0 3 0 0 0 1 0 0 8

06LM308Qb 18 0 0 6 0 0 0 8 0 37 0 45 0 15 0 0 0 1 0 0 16

06LM308Q 19 0 0 6 0 0 0 10 0 38 0 48 0 14 0 0 0 1 0 0 12

06LM310Q 6 0 0 11 0 0 0 14 7 0 0 21 3 12 0 0 0 0 0 9 39 epistilbite

06LM311Q 11 34 0 0 0 0 0 0 9 6 0 15 0 0 0 0 0 1 0 0 39

06LM292Q 4 11 7 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 78

06LM293Q 69 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 30 hematite

06LM295Q 7 2 0 0 0 0 0 0 0 10 0 10 0 3 0 0 53 0 0 0 78

06LM296Q 42 2 0 0 0 0 21 21 0 0 0 42 0 0 0 0 0 1 0 0 13

06LM297Q 20 0 0 0 0 0 13 25 0 0 0 38 0 0 0 0 0 1 0 0 42

06LM298Q 19 0 0 0 44 0 17 0 0 0 0 17 0 0 0 0 0 0 0 2 18 hematite

06LM299Q 42 0 0 27 0 0 0 0 7 0 0 7 0 0 0 0 0 1 0 0 24

06LM312Q 33 0 0 0 0 0 11 36 0 0 0 46 16 2 0 0 0 0 0 0 3 hematite?

04LM131Q 21 2 0 0 5 0 56 0 0 0 0 56 3 0 0 0 0 2 0 0 12

04LM132Q 18 2 0 0 0 0 0 24 18 5 0 48 0 0 0 0 0 0 0 0 32

04LM087Q 9 2 0 0 0 0 0 0 22 0 0 22 0 0 0 0 0 2 0 0 65

04LM088Q 13 2 0 0 0 0 0 0 9 10 0 18 0 0 0 0 0 0 0 0 66


44



K-

fsp aug chl mon cel mag act others NQ

06LM284 23 0 0 0 0 0 22 39 0 0 0 60 0 0 0 0 0 1 0 0 15

04LM015Q 22 0 9 58 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 11

06LM303Q 3 0 28 0 3 0 15 12 0 0 0 27 4 0 0 0 0 1 0 0 35

06LM313Q 41 0 22 0 0 0 0 11 0 0 0 11 1 0 0 0 0 1 0 0 24

06LM314Q 32 0 18 0 0 0 0 0 18 0 0 18 0 0 0 0 0 1 0 0 31

06LM315Q 4 0 50 0 0 0 0 4 0 0 0 4 0 4 0 0 0 1 0 0 37

04LM089Q 6 8 32 0 0 0 0 7 0 0 0 7 0 5 0 0 13 0 0 0 42

06LM317Q 45 20 0 0 15 0 9 0 0 0 0 9 0 0 0 0 0 0 0 0 11

04LM090Q 43 16 7 4 0 0 0 4 0 0 0 4 0 4 0 0 0 0 0 0 21

06LM321Q 23 2 47 0 0 0 0 10 0 0 0 10 0 4 0 0 0 0 0 0 14

06LM323Q 12 26 12 0 0 0 0 11 0 23 0 34 0 0 0 0 0 1 0 0 14

06LM324Q 34 30 3 0 0 0 0 5 0 0 0 5 0 0 0 0 0 0 0 0 28

06LM325Q 6 11 7 8 0 0 0 0 0 9 12 9 0 2 0 0 0 2 0 0 43

04LM116Q 39 0 9 0 0 0 0 0 10 0 0 10 0 0 0 0 0 1 0 0 41

06LM319Q 8 0 33 0 4 0 18 0 0 0 0 18 3 0 0 0 0 1 0 0 33

06LM285 31 0 0 0 19 0 12 26 0 0 0 38 0 0 0 0 0 1 0 0 10

04LM094Q 7 0 0 0 22 0 24 0 0 0 0 24 0 16 0 0 0 0 0 0 32

04LM149Q 20 19 13 0 0 0 0 22 0 0 0 22 0 4 0 0 0 0 0 0 21

04LM023Q 41 0 19 0 0 0 0 5 0 5 0 9 0 3 0 0 0 1 0 0 27

04LM142Q 5 0 0 0 0 0 0 0 0 13 0 13 0 9 0 0 0 2 0 0 72

04LM025Q 5 0 40 0 0 0 0 11 11 0 0 22 3 5 0 0 6 1 0 0 23

04LM143Q 5 0 27 0 0 0 0 16 0 14 0 29 6 5 0 0 7 2 0 0 24

04LM026Q 0 3 10 9 2 14 0 0 0 22 22 22 0 0 39 9 0 0 0 5 2

05RS001aQ 0 4 16 0 9 0 7 27 0 0 0 34 9 10 0 0 0 2 0 0 16

05RS003bQ 0 4 23 0 6 0 9 23 0 0 0 32 8 9 0 0 0 1 0 0 15

05RS004Q 3 4 0 0 21 0 10 27 0 0 0 37 8 9 0 0 0 2 0 0 17

05RS005Q 0 3 17 0 9 0 10 23 0 0 0 33 9 10 0 0 0 1 0 0 18

05RS006Q 0 4 23 0 7 0 13 18 0 0 0 31 8 10 0 0 0 1 0 0 17

05RSK008 1 5 31 0 4 0 7 23 0 0 0 30 4 10 0 0 0 1 0 0 15

45



K-

fsp aug chl mon cel mag act others NQ

05RS009Q 7 3 27 0 0 0 0 17 19 0 0 36 5 8 0 0 0 2 0 0 12

05RS010aQ 6 0 66 0 0 0 0 0 0 6 0 6 0 5 0 0 0 0 0 0 18

05RS010bQ 11 3 39 4 0 0 0 4 0 12 0 16 0 6 0 0 0 0 0 0 21

05RS011q 17 2 51 7 0 0 0 4 0 0 0 4 0 0 0 0 0 0 0 0 19

05RS012q 14 3 16 0 0 0 0 13 0 22 0 34 7 6 0 0 0 1 0 0 19

05RS013Q 2 3 18 4 0 0 6 25 0 0 0 31 9 10 0 0 0 1 0 0 21

05RS014Q 3 3 37 0 0 0 0 14 14 0 0 28 5 7 0 0 0 1 0 0 16

05RS015q 5 2 33 0 0 0 0 8 13 12 0 33 5 6 0 0 0 1 0 0 14

05RS016Q 12 1 35 9 0 0 0 7 0 17 0 24 0 4 0 0 0 1 0 0 13

05RS017q 13 0 58 14 0 0 0 4 0 0 0 4 0 0 0 0 0 0 0 0 11

05RS018Q 16 3 31 0 0 0 0 0 0 23 0 23 0 5 0 0 0 1 0 0 21

05RS019Q 12 7 17 2 0 0 0 15 0 28 0 43 8 5 0 0 0 1 0 0 5

05RS020Q 8 7 24 4 0 0 0 11 15 7 0 33 5 5 0 0 0 1 0 0 11

05RS021Q 55 21 0 0 0 0 0 6 0 0 0 6 3 2 0 0 0 0 0 0 14

05RS022Q 44 4 23 0 0 0 0 4 0 0 0 4 3 0 0 0 0 0 0 0 22

05RS025Q 37 1 22 0 0 0 0 8 0 0 0 8 5 3 0 0 0 0 0 0 24

04LM080Q 41 0 24 0 0 0 0 9 0 0 0 9 6 0 0 0 0 0 0 0 20

04LM078Q 11 4 24 11 0 0 0 7 0 18 0 25 5 5 0 0 0 0 0 0 15

04LM064Q 0 0 0 0 6 24 0 23 0 0 0 23 0 13 0 0 0 0 0 0 35

04LM144Q 0 3 0 0 0 40 0 4 0 0 0 4 4 20 0 0 0 2 0 0 27

04LM068Q 9 0 36 0 0 0 0 26 0 0 0 26 0 5 0 0 0 0 0 0 24

04LM069Q 65 0 4 0 0 0 0 3 0 0 0 3 0 2 0 0 0 0 0 0 25

04LM070Q 50 0 19 0 0 0 0 9 0 0 0 9 0 0 0 0 0 0 0 0 23

04LM073Q 37 0 25 0 0 0 0 6 0 10 0 15 1 0 0 0 0 0 0 0 20

04LM074Q 11 3 24 0 0 0 0 0 0 21 0 21 2 5 0 0 0 0 0 0 34

04LM075Q 66 0 25 0 0 0 0 5 0 0 0 5 0 0 0 0 0 0 0 0 4

04LM041Q 5 0 20 0 0 0 0 6 9 0 0 15 3 6 0 0 15 1 0 0 49

04LM042Q 55 1 10 0 0 0 0 0 8 4 0 13 0 0 0 0 0 0 0 0 22

04LM091Q 49 13 0 0 0 0 0 0 16 0 0 16 0 0 0 0 0 1 0 0 21

04LM092Q 44 40 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 16

04LM147Q 2 0 0 0 0 0 0 0 0 22 0 22 0 11 0 0 0 2 0 0 63

04LM148Q 21 0 9 0 0 0 0 0 20 17 0 36 4 0 0 0 0 2 0 0 28


46

4.2.3 Río Derecha - Río Zamoreño

Rio Derecha

sample name qua cal heu mor alb byt Pla Adu vel mag NQ

09LM090 26 0 12 34 3 2 7 0 0 1 14

09LM091 21 0 61 2 0 2 6 0 6 0 12

09LM092 13 2 5 29 0 4 17 0 0 1 31

09LM093 21 2 3 44 0 2 6 3 0 1 18

Rio Zamoreño

sample

name qua cal heu mor lau ana alb oli lab byt pla aug mag pum pre NQ

09LM104Q 9 0 46 0 0 0 11 0 0 0 0 4 0 0 0 30

09LM105Q 7 0 45 0 0 0 5 0 5 0 5 5 0 0 0 33

09LM106K x

09LM107Q 7 0 52 0 0 0 4 0 4 0 4 5 0 0 0 22

09LM108Q 11 0 27 21 0 0 2 0 3 0 3 3 0 0 0 32

09LM109 8 0 21 35 0 1 0 1 3 0 4 3 0 0 0

09LM110Q 38 0 5 28 0 2 0 0 2 0 2 2 0 0 0 23

09LM111K x x x x x

09LM113Q 13 0 11 37 0 0 2 0 2 3 6 3 0 0 0 28

09LM114Q 22 2 44 3 0 0 4 0 1 2 3 4 0 0 0 17

09LM115Q 32 7 11 2 2 6 5 0 24 0 24 4 0 0 0 7

09LM116K x x

09LM118Q 29 0 0 0 0 0 50 0 0 0 0 2 1 5 1 11

09LM119Q 16 1 0 0 0 0 59 0 0 0 0 3 2 4 0 15

47

4.2.4 Manabí área

Agua Blanca, Puerto Cayo, Puerto López and Río Mocora

Sample Names qua cal heu mor ana lau tho sti eri epi alb oli and lab byt pla k-

fsp aug ens mag cri try NQ

CZ35 12 4 6 0 0 0 0 0 0 0 0 0 0 9 0 9 0 0 0 0 24 16 22

EC06LM428

bis 2 1 16 0 1 0 0 0 24 0 0 0 5 10 0 14 0 6 0 1 0 0 21

EC06LM430 2 2 16 0 1 0 0 0 14 0 0 0 11 7 0 18 1 7 0 1 0 0 19

EC06LM430

bis 10 7 0 0 0 0 0 0 0 0 0 0 2 0 0 2 2 0 0 0 27 55 0

EC06LM431 1 4 36 0 0 0 0 0 0 0 3 0 12 0 0 12 4 8 0 1 0 0 18

EC06LM431bi 1 3 34 0 0 0 0 0 0 0 3 0 12 0 0 12 3 8 0 1 0 0 22

05RS137 1 0 10 0 3 0 0 0 0 0 0 1 7 23 2 33 14 7 0 0 0 0 0

05RS139 1 0 28 0 0 0 0 0 6 0 0 0 0 17 0 17 6 5 0 0 0 0 20

CZ33 3 2 37 0 0 0 0 0 0 0 0 7 0 0 0 7 0 0 0 0 0 0 43

EC06LM427 1 5 22 0 0 0 0 0 6 0 0 0 0 2 0 2 26 5 0 2 0 0 31

EC06LM428 1 12 78 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 7

EC06LM406 0 0 0 0 2 1 2 9 0 7 0 32 0 0 0 32 3 0 0 0 0 0 12

EC06LM407 3 8 49 0 0 0 0 0 0 0 2 0 8 0 0 8 1 4 0 1 0 0 15

EC06LM411 3 0 32 27 0 0 0 0 0 0 0 0 8 0 0 8 1 3 0 1 0 0 16

EC06LM421 3 0 47 0 0 0 0 0 0 0 0 0 17 0 0 17 0 3 0 1 0 0 13

EC06LM424 1 4 53 0 0 0 0 0 0 0 1 0 7 0 0 7 7 4 0 1 0 0 16

EC06LM425 2 1 45 0 0 0 0 0 0 0 2 2 13 12 2 29 6 4 3 0 0 0 0


48

Río Ayampe

Sample

names qua cal heu mor ana lau tho sti cha alb oli and lab byt pla

K-

fsp aug dio pum ens fer mag NQ

04LM049Q 1 0 7 0 12 0 13 0 0 0 0 0 17 0 17 2 33 0 0 0 0 1 0

04LM059 16 5 0 0 19 0 0 0 0 2 4 12 14 0 30 0 0 4 0 0 0 0 0

04LMXP2 1 1 84 0 0 0 0 0 0 0 0 4 5 0 9 0 0 0 0 0 0 0 0

04LMXP3 0 0 93 0 0 0 0 0 0 0 0 2 1 0 3 0 0 0 0 0 0 0 1

05RS065 0 0 0 0 7 0 0 0 15 3 0 0 0 18 18 3 37 0 0 0 0 0 0

05RS071 1 0 98 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1

05RS091b 11 2 24 26 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 35

05RS101 4 0 51 29 0 0 0 0 0 0 0 0 0 0 0 0 3 0 0 0 0 0 13

05RS110 3 5 35 5 3 0 0 0 0 0 0 8 12 2 22 3 8 0 0 0 0 0 0

05RS114 9 7 27 31 0 0 0 0 0 0 0 0 14 0 14 2 0 0 0 0 0 0 0

06LM337 38 0 0 0 0 9 0 0 0 29 9 0 0 0 9 4 3 0 0 0 0 0 1

06LM341 26 0 0 2 0 14 0 0 0 11 25 0 0 0 25 4 4 0 0 0 0 0 0

06LM343 39 1 24 0 0 0 0 22 0 6 0 0 0 0 0 1 2 0 0 0 0 0 5

06LM345 11 0 18 9 0 0 0 2 0 0 6 6 17 0 29 3 7 0 0 0 0 1 0

06LM347 33 3 0 47 0 0 0 0 0 0 1 1 0 0 2 3 0 0 0 0 0 0 11

06LM350 41 2 0 0 0 0 0 0 0 33 0 0 0 0 0 8 2 0 0 0 0 0 13

06LM351 43 0 0 0 0 33 0 0 0 15 0 0 0 0 0 2 3 0 0 0 0 0 5

06LM378 3 3 22 0 0 0 0 0 0 2 1 2 22 2 27 7 9 0 0 0 0 1 0

06LM396 2 18 46 4 0 0 0 0 0 0 0 0 14 0 14 2 6 0 0 0 0 0 0

06LM397 8 5 27 46 0 0 0 0 0 0 0 0 2 0 2 2 1 0 0 0 0 0 8

EC06LM402 0 0 0 0 20 8 4 3 0 0 0 0 0 0 0 2 31 0 0 0 0 1 31

EC06LM404 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 27 2 5 3 0 63

49

4.3 EPMA

4.3.1 HEU-type zeolites

1.

Sample 06LM015

Num 6 7 1 2 3 4 5 6 7 8

Na2O 0.07 0.25 0.05 0.26 0.24 0.20 0.72 1.88 0.24 0.38

K2O 0.49 0.38 0.40 0.49 0.52 0.47 0.16 0.20 0.21 0.16

SiO2 59.79 59.43 59.29 59.21 59.56 58.52 64.75 66.07 66.99 65.68

Al2O3 16.02 16.28 15.84 16.13 15.78 16.22 13.10 13.42 12.44 12.61

FeO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

MnO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

MgO 0.42 0.00 0.02 0.03 0.03 0.00 0.72 0.03 0.69 0.73

CaO 7.44 7.82 7.92 7.77 7.81 7.65 5.30 4.41 5.40 5.46

SrO 0.32 0.43 0.29 0.36 0.33 0.37 0.00 0.00 0.00 0.00

BaO 0.00 0.63 0.64 0.70 0.39 0.74 0.00 0.00 0.00 0.00

Na 0.06 0.22 0.04 0.24 0.22 0.18 0.63 1.62 0.21 0.33

K 0.29 0.22 0.24 0.29 0.30 0.28 0.09 0.11 0.12 0.09

Si 27.41 27.26 27.40 27.27 27.43 27.20 29.10 29.26 29.56 29.36

Al 8.65 8.80 8.63 8.75 8.56 8.89 6.94 7.01 6.47 6.64

Fe 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Mn 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Mg 0.28 0.00 0.02 0.02 0.02 0.00 0.48 0.02 0.45 0.49

Ca 3.65 3.84 3.92 3.83 3.86 3.81 2.55 2.09 2.56 2.61

Sr 0.09 0.12 0.08 0.09 0.09 0.10 0.00 0.00 0.00 0.00

Ba 0.00 0.11 0.11 0.13 0.07 0.13 0.00 0.00 0.00 0.00

E% 3.05 2.52 1.08 0.88 -0.27 3.91 2.26 17.79 2.02 0.33

Si/Al 3.17 3.10 3.18 3.11 3.20 3.06 4.19 4.18 4.57 4.42

R 0.76 0.76 0.76 0.76 0.76 0.75 0.81 0.81 0.82 0.82

M/M+D 0.08 0.10 0.06 0.11 0.11 0.10 0.19 0.45 0.10 0.12

Na/Na+K 0.18 0.50 0.15 0.45 0.42 0.40 0.87 0.94 0.64 0.79

50

2.

Sample 06LM027

Num 9 10 14 15 16 17 35 36 37 38

Na2O 0.25 0.12 0.20 0.20 0.40 0.20 0.24 0.60 0.29 0.30

K2O 0.15 0.15 0.19 0.20 0.18 0.18 0.37 0.44 0.52 0.38

SiO2 66.52 67.15 66.58 65.92 66.13 67.36 66.74 65.42 60.90 63.39

Al2O3 12.80 12.64 13.26 12.91 12.67 13.41 12.86 12.92 15.35 14.02

FeO 0.00 0.00 0.11 0.22 0.00 0.00 0.00 0.10 0.00 0.00

MnO 0.00 0.08 0.12 0.00 0.00 0.00 0.00 0.00 0.00 0.00

MgO 0.92 0.26 0.53 0.48 0.42 0.95 0.36 0.16 0.04 0.00

CaO 5.35 6.15 6.11 6.04 6.27 5.58 6.11 6.23 8.12 7.09

SrO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.09 0.00

BaO 0.00 0.00 0.00 0.00 0.00 0.30 0.00 0.00 0.00 0.00

Na 0.21 0.10 0.17 0.17 0.34 0.17 0.21 0.52 0.25 0.26

K 0.08 0.08 0.11 0.11 0.10 0.10 0.21 0.25 0.30 0.22

Si 29.36 29.50 29.15 29.23 29.30 29.17 29.34 29.16 27.69 28.58

Al 6.66 6.55 6.84 6.75 6.62 6.85 6.66 6.79 8.22 7.45

Fe 0.00 0.00 0.04 0.08 0.00 0.00 0.00 0.04 0.00 0.00

Mn 0.00 0.03 0.04 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Mg 0.61 0.17 0.34 0.31 0.27 0.61 0.24 0.11 0.03 0.00

Ca 2.53 2.89 2.87 2.87 2.97 2.59 2.88 2.97 3.96 3.42

Sr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.00

Ba 0.00 0.00 0.00 0.00 0.00 0.05 0.00 0.00 0.00 0.00

E% 1.32 3.88 2.85 2.57 -4.68 0.97 0.30 -1.57 -4.02 1.68

Si/Al 4.41 4.51 4.26 4.33 4.43 4.26 4.40 4.30 3.37 3.84

R 0.82 0.82 0.81 0.81 0.82 0.81 0.81 0.81 0.77 0.79

M/M+D 0.09 0.06 0.08 0.08 0.12 0.08 0.12 0.20 0.12 0.12

Na/Na+K 0.72 0.56 0.61 0.61 0.77 0.63 0.50 0.67 0.46 0.55

51

3.

Sample 06LM026

Num 39 41 42 57 58 59 60 61 62 63

Na2O 0.30 0.21 0.25 0.16 0.20 0.27 0.50 0.35 0.26 0.38

K2O 0.43 0.21 0.25 0.15 0.30 0.36 0.76 0.49 0.56 0.27

SiO2 61.24 66.14 65.97 68.16 67.95 67.54 59.47 60.40 60.68 67.27

Al2O3 15.21 12.73 12.67 12.00 12.29 12.14 16.40 15.29 15.21 11.99

FeO 0.00 0.00 0.13 0.23 0.23 0.49 0.00 0.00 0.10 0.00

MnO 0.07 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

MgO 0.00 0.00 0.38 0.86 1.15 1.15 0.00 0.00 0.00 0.38

CaO 8.02 6.72 6.12 5.31 5.21 4.82 8.12 8.14 8.11 5.88

SrO 0.00 0.00 0.00 0.00 0.00 0.00 0.34 0.16 0.21 0.00

BaO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.36 0.00

Na 0.27 0.18 0.21 0.14 0.17 0.23 0.44 0.31 0.23 0.33

K 0.25 0.12 0.14 0.08 0.17 0.20 0.44 0.29 0.33 0.15

Si 27.80 29.34 29.33 29.75 29.56 29.60 27.14 27.65 27.67 29.69

Al 8.14 6.66 6.64 6.18 6.30 6.27 8.82 8.25 8.17 6.24

Fe 0.00 0.00 0.05 0.08 0.08 0.18 0.00 0.00 0.04 0.00

Mn 0.03 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Mg 0.00 0.00 0.25 0.56 0.75 0.75 0.00 0.00 0.00 0.25

Ca 3.90 3.19 2.91 2.48 2.43 2.26 3.97 3.99 3.96 2.78

Sr 0.00 0.00 0.00 0.00 0.00 0.00 0.09 0.04 0.06 0.00

Ba 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.06 0.00

E% -2.21 -0.49 0.12 -0.81 -4.46 0.00 -1.98 -4.77 -5.83 -4.59

Si/Al 3.42 4.41 4.42 4.82 4.69 4.72 3.08 3.35 3.39 4.76

R 0.77 0.82 0.82 0.83 0.82 0.83 0.75 0.77 0.77 0.83

M/M+D 0.12 0.09 0.10 0.07 0.09 0.12 0.18 0.13 0.12 0.14

Na/Na+K 0.52 0.60 0.60 0.62 0.50 0.53 0.50 0.52 0.41 0.68

52

4.

Sample 06LM026

Num 64 65 66 67 69 70 71 72 73 74

Na2O 0.26 0.25 0.24 0.26 0.29 0.26 0.24 0.31 0.34 0.32

K2O 0.24 0.28 0.22 0.19 0.25 0.24 0.25 0.35 0.27 0.24

SiO2 61.73 64.07 67.99 68.92 65.01 65.68 64.76 66.65 64.83 64.50

Al2O3 14.65 12.73 13.29 12.94 12.68 12.97 12.67 12.85 12.85 12.89

FeO 0.00 0.00 0.00 0.13 0.00 0.00 0.00 0.00 0.10 0.00

MnO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

MgO 0.03 0.35 1.06 0.53 0.00 0.06 0.04 0.00 0.00 0.00

CaO 7.91 6.12 5.55 5.87 6.57 6.55 6.64 6.69 6.74 6.81

SrO 0.09 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

BaO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Na 0.23 0.22 0.20 0.21 0.25 0.22 0.21 0.27 0.30 0.28

K 0.14 0.16 0.12 0.10 0.14 0.14 0.14 0.20 0.16 0.14

Si 28.07 29.17 29.25 29.49 29.27 29.23 29.24 29.31 29.14 29.11

Al 7.85 6.83 6.74 6.53 6.73 6.80 6.74 6.66 6.81 6.85

Fe 0.00 0.00 0.00 0.05 0.00 0.00 0.00 0.00 0.04 0.00

Mn 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Mg 0.02 0.24 0.68 0.34 0.00 0.04 0.03 0.00 0.00 0.00

Ca 3.85 2.99 2.56 2.69 3.17 3.12 3.21 3.15 3.24 3.29

Sr 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Ba 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

E% -3.73 0.02 -0.82 3.04 0.04 1.85 -1.22 -1.55 -1.45 -2.17

Si/Al 3.58 4.27 4.34 4.52 4.35 4.30 4.34 4.40 4.28 4.25

R 0.78 0.81 0.81 0.82 0.81 0.81 0.81 0.81 0.81 0.81

M/M+D 0.09 0.11 0.09 0.09 0.11 0.10 0.10 0.13 0.12 0.11

Na/Na+K 0.62 0.57 0.63 0.68 0.64 0.62 0.59 0.58 0.66 0.67

53

5.

Sample 06LM026

Num 75 90 91 92 93 94 95 117 118 120

Na2O 0.23 0.33 0.32 0.28 0.19 0.42 0.28 0.31 0.42 0.71

K2O 0.34 0.31 0.26 0.29 0.24 0.28 0.26 0.41 0.55 0.69

SiO2 61.40 60.81 64.10 64.72 65.60 65.08 66.34 60.19 60.13 59.44

Al2O3 14.61 14.86 12.60 12.67 12.79 12.47 12.23 14.90 15.55 16.40

FeO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

MnO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

MgO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

CaO 7.83 8.15 6.75 6.83 6.63 6.61 6.54 7.93 8.07 8.20

SrO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.10 0.16 0.26

BaO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Na 0.21 0.29 0.28 0.24 0.17 0.37 0.24 0.27 0.38 0.63

K 0.20 0.18 0.15 0.17 0.14 0.16 0.15 0.24 0.32 0.40

Si 28.08 27.86 29.18 29.20 29.29 29.31 29.53 27.81 27.53 27.10

Al 7.87 8.03 6.76 6.74 6.73 6.62 6.42 8.12 8.39 8.81

Fe 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Mn 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Mg 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Ca 3.84 4.00 3.29 3.30 3.17 3.19 3.12 3.93 3.96 4.00

Sr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.03 0.04 0.07

Ba 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

E% -2.57 -5.20 -3.63 -3.88 1.28 -4.20 -3.08 -3.64 -3.56 -3.94

Si/Al 3.57 3.47 4.32 4.33 4.35 4.43 4.60 3.43 3.28 3.07

R 0.78 0.78 0.81 0.81 0.81 0.82 0.82 0.77 0.77 0.75

M/M+D 0.10 0.10 0.11 0.11 0.09 0.14 0.11 0.12 0.15 0.20

Na/Na+K 0.51 0.62 0.65 0.59 0.55 0.69 0.62 0.53 0.54 0.61

54

6.

Sample 06LM026

Num 121 122 123 124 125 126 127 128 129 130

Na2O 0.26 0.41 0.50 0.24 0.22 0.25 0.25 0.28 0.36 0.31

K2O 0.63 0.71 0.24 0.59 0.25 0.24 0.23 0.24 0.53 0.42

SiO2 58.83 59.42 63.48 59.55 66.30 66.36 65.50 66.89 60.55 61.68

Al2O3 15.90 16.33 13.76 15.71 12.86 13.29 13.81 12.56 15.34 15.29

FeO 0.00 0.00 0.00 0.00 0.00 0.10 0.00 0.00 0.00 0.00

MnO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

MgO 0.00 0.00 0.03 0.03 0.16 0.69 0.04 0.03 0.00 0.00

CaO 8.15 8.15 7.52 8.47 6.63 6.12 7.21 6.78 8.17 8.25

SrO 0.22 0.33 0.00 0.21 0.00 0.00 0.00 0.00 0.16 0.00

BaO 0.32 0.40 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Na 0.23 0.36 0.44 0.22 0.19 0.21 0.21 0.24 0.32 0.27

K 0.37 0.42 0.14 0.35 0.14 0.13 0.13 0.13 0.31 0.24

Si 27.25 27.14 28.56 27.36 29.27 29.08 28.83 29.42 27.64 27.79

Al 8.68 8.79 7.29 8.51 6.69 6.86 7.17 6.51 8.25 8.12

Fe 0.00 0.00 0.00 0.00 0.00 0.04 0.00 0.00 0.00 0.00

Mn 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Mg 0.00 0.00 0.02 0.02 0.11 0.45 0.03 0.02 0.00 0.00

Ca 4.05 3.99 3.63 4.17 3.14 2.88 3.40 3.19 3.99 3.98

Sr 0.06 0.09 0.00 0.06 0.00 0.00 0.00 0.00 0.04 0.00

Ba 0.06 0.07 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

E% -2.84 -3.06 -7.33 -5.95 -1.82 -1.41 -0.42 -4.25 -5.19 -4.13

Si/Al 3.14 3.09 3.92 3.22 4.37 4.24 4.02 4.52 3.35 3.42

R 0.76 0.76 0.80 0.76 0.81 0.81 0.80 0.82 0.77 0.77

M/M+D 0.13 0.16 0.14 0.12 0.09 0.09 0.09 0.10 0.14 0.11

Na/Na+K 0.38 0.46 0.76 0.39 0.57 0.61 0.62 0.64 0.51 0.52

55

4.3.2 Mordenite

Sample 04LM026 04LM015

Num 104 105 106 107 1 2 3 4

Na2O 1.16 1.12 0.95 0.79 1.11 1.22 1.49 1.59

K2O 0.18 0.25 0.24 0.23 0.11 0.06 0.08 0.05

SiO2 60.72 57.54 63.60 68.47 68.42 68.41 67.62 68.03

Al2O3 11.12 10.83 11.45 11.74 12.77 12.52 12.99 12.58

FeO 0.22 0.16 0.24 0.25 0.00 0.00 0.00 0.00

MnO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

MgO 0.19 0.19 0.05 0.06 0.00 0.00 0.00 0.00

CaO 3.55 3.46 3.84 3.61 3.96 3.92 4.10 4.01

TiO2 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

SrO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

BaO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

H2O 22.87 26.43 19.62 14.85 13.64 13.86 13.73 13.74

Na 1.48 1.50 1.15 0.90 1.25 1.38 1.69 1.80

K 0.15 0.22 0.19 0.17 0.08 0.05 0.06 0.04

Si 39.76 39.57 39.93 40.38 39.86 39.95 39.56 39.78

Al 8.58 8.78 8.48 8.16 8.77 8.62 8.96 8.67

Fe 0.12 0.09 0.13 0.12 0.00 0.00 0.00 0.00

Mn 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Mg 0.19 0.19 0.05 0.05 0.00 0.00 0.00 0.00

Ca 2.49 2.55 2.58 2.28 2.47 2.45 2.57 2.51

Ti 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Sr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Ba 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Si/Al 4.63 4.51 4.71 4.95 4.55 4.64 4.42 4.59

R 0.82 0.82 0.82 0.83 0.82 0.82 0.82 0.82

E% 24.42 23.08 30.24 44.22 39.71 36.14 30.05 26.16

56

4.3.3 Laumontite

Sample 04LM094

Num 26 27 28 30 31 33

Na2O 0.19 0.14 0.14 0.24 0.00 0.00

K2O 0.53 0.40 0.37 0.41 0.06 0.06

SiO2 53.17 52.85 52.14 53.36 51.63 51.18

Al2O3 20.88 21.07 20.97 21.16 21.62 21.75

FeO 0.11 0.16 0.48 0.00 0.00 0.00

MnO 0.00 0.00 0.00 0.00 0.00 0.00

MgO 0.00 0.00 0.32 0.00 0.00 0.00

CaO 11.17 11.24 11.37 11.39 12.26 12.31

TiO2 0.00 0.00 0.24 0.00 0.00 0.00

SrO 0.00 0.00 0.00 0.00 0.00 0.00

BaO 0.00 0.00 0.00 0.00 0.00 0.00

H2O 13.95 14.16 13.98 13.46 14.44 14.70

Na 0.12 0.08 0.08 0.14 0.00 0.00

K 0.21 0.16 0.14 0.16 0.02 0.02

Si 16.38 16.31 16.13 16.33 16.02 15.95

Al 7.58 7.67 7.65 7.63 7.91 7.99

Fe 0.03 0.04 0.13 0.00 0.00 0.00

Mn 0.00 0.00 0.00 0.00 0.00 0.00

Mg 0.00 0.00 0.15 0.00 0.00 0.00

Ca 3.69 3.72 3.77 3.74 4.08 4.11

Ti 0.00 0.00 0.06 0.00 0.00 0.00

Sr 0.00 0.00 0.00 0.00 0.00 0.00

Ba 0.00 0.00 0.00 0.00 0.00 0.00

Si/AL 2.16 2.13 2.11 2.14 2.03 2.00

R 0.68 0.68 0.68 0.68 0.67 0.67

E% -1.12 0.46 -3.60 -1.76 -3.31 -3.13

57

4.3.4 Chlorite-Smectite

1.

Sample 04LM094

Num 18 20 21 23 29

Na2O 0.00 0.05 0.07 0.11 0.04

K2O 0.30 0.45 0.05 0.07 0.30

SiO2 27.90 30.98 29.83 29.71 27.30

Al2O3 11.38 12.39 11.29 11.04 11.13

FeO 19.76 20.09 25.41 23.94 19.71

MnO 0.27 0.33 0.63 0.60 0.33

MgO 13.10 12.10 15.17 14.46 12.91

CaO 1.12 5.36 1.05 1.04 1.12

TiO2 0.10 0.64 0.06 0.00 0.07

SrO 0.00 0.00 0.00 0.00 0.00

BaO 0.23 0.00 0.00 0.00 0.00

H2O 25.84 17.62 16.45 19.05 27.09

Na 0.00 0.02 0.03 0.05 0.02

K 0.09 0.13 0.01 0.02 0.10

Si 6.87 6.91 6.67 6.80 6.84

Al 3.30 3.26 2.97 2.98 3.29

Fe 4.07 3.75 4.75 4.58 4.13

Mn 0.06 0.06 0.12 0.12 0.07

Mg 4.81 4.02 5.05 4.94 4.82

Ca 0.29 1.28 0.25 0.25 0.30

Ti 0.02 0.11 0.01 0.00 0.01

Sr 0.00 0.00 0.00 0.00 0.00

Ba 0.02 0.00 0.00 0.00 0.00

Tot K + Ca +

Na 0.39 1.43 0.30 0.32 0.41

Al Vi 1.13 1.09 1.33 1.20 1.16

Al Vi 2.17 2.17 1.64 1.78 2.13

Tot iv 8.00 8.00 8.00 8.00 8.00

Tot Vi 11.12 10.11 11.57 11.42 11.16

Fe/(Fe + Mg) 0.46 0.48 0.48 0.48 0.46

58

2.

Sample 04LM026

Num 76 77 78 79 80 81 82 84 85 86 87

Na2O 0.07 0.06 0.20 0.18 0.13 0.13 0.12 0.06 0.10 0.11 0.14

K2O 0.07 0.04 0.19 0.11 0.47 0.74 0.31 0.23 0.50 0.33 0.22

SiO2 29.90 28.17 33.23 30.19 29.36 31.28 28.95 27.44 29.20 27.86 29.03

Al2O3 12.40 11.88 11.79 12.40 11.15 11.15 11.27 10.82 11.04 10.33 11.14

FeO 28.72 27.40 25.75 28.01 21.63 22.12 21.49 20.42 20.91 18.95 21.33

MnO 1.39 1.29 0.89 1.33 0.67 0.56 0.53 0.55 0.62 0.51 0.57

MgO 13.26 12.42 13.07 12.83 11.67 11.67 11.77 11.12 11.13 11.36 11.78

CaO 0.80 0.60 1.69 0.91 1.53 1.81 1.62 1.38 2.77 1.42 1.40

TiO2 0.00 0.00 0.00 0.00 0.00 0.10 0.00 0.00 0.07 0.00 0.00

SrO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

BaO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.38

H2O 13.40 18.13 13.19 14.06 23.40 20.44 23.96 28.00 23.67 29.15 24.01

Na 0.03 0.03 0.08 0.08 0.06 0.06 0.05 0.03 0.05 0.05 0.07

K 0.02 0.01 0.05 0.03 0.14 0.22 0.09 0.07 0.15 0.11 0.07

Si 6.56 6.54 7.09 6.65 7.05 7.22 7.00 7.00 7.05 7.16 7.03

Al 3.21 3.25 2.97 3.22 3.16 3.03 3.21 3.25 3.14 3.13 3.18

Fe 5.27 5.32 4.60 5.16 4.35 4.27 4.34 4.35 4.22 4.07 4.32

Mn 0.26 0.25 0.16 0.25 0.14 0.11 0.11 0.12 0.13 0.11 0.12

Mg 4.34 4.30 4.16 4.21 4.18 4.02 4.24 4.23 4.01 4.35 4.26

Ca 0.19 0.15 0.39 0.21 0.39 0.45 0.42 0.38 0.72 0.39 0.36

Ti 0.00 0.00 0.00 0.00 0.00 0.02 0.00 0.00 0.01 0.00 0.00

Sr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Ba 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.04

Tot

K+Ca+N

a

0.24 0.19 0.52 0.32 0.60 0.72 0.57 0.48 0.92 0.55 0.50

Al Vi 1.44 1.46 0.91 1.35 0.95 0.78 1.00 1.00 0.95 0.84 0.97

Al Vi 1.77 1.79 2.06 1.86 2.21 2.26 2.21 2.25 2.19 2.28 2.22

Tot iv 8.00 8.00 8.00 8.00 8.00 8.00 8.00 8.00 8.00 8.00 8.00

Tot Vi 11.63 11.66 10.97 11.48 10.87 10.67 10.90 10.95 10.56 10.81 10.91

Fe /

(Fe+Mg) 0.55 0.55 0.52 0.55 0.51 0.52 0.51 0.51 0.51 0.48 0.50

59

3.

Sample 04LM026

Num 88 89 98 99 100 102 103 108 109 110 111

Na2O 0.07 0.17 0.15 0.11 0.16 0.07 0.10 0.10 0.14 0.09 0.08

K2O 0.05 0.16 0.44 0.27 0.46 0.60 0.40 0.36 0.38 0.24 0.29

SiO2 29.85 30.32 29.55 26.47 33.77 31.58 31.59 35.07 35.25 27.33 29.70

Al2O3 12.56 12.44 11.18 10.14 12.36 10.88 11.83 10.12 9.78 10.60 11.23

FeO 28.31 28.11 21.37 19.87 23.89 21.41 23.42 21.48 21.33 20.62 20.81

MnO 1.23 1.28 0.46 0.50 0.59 0.41 0.59 0.50 0.55 0.42 0.47

MgO 13.53 12.47 12.02 10.53 12.92 11.57 12.14 13.07 14.10 11.06 11.59

CaO 0.59 0.85 1.54 1.13 2.08 2.89 2.23 2.56 2.25 1.16 1.59

TiO2 0.00 0.00 0.00 0.00 0.00 0.00 0.07 0.00 0.00 0.00 0.08

SrO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

BaO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

H2O 13.81 14.19 23.29 30.97 13.77 20.59 17.62 16.73 16.23 28.48 24.15

Na 0.03 0.07 0.07 0.06 0.07 0.03 0.04 0.04 0.06 0.04 0.04

K 0.01 0.04 0.13 0.09 0.12 0.18 0.12 0.10 0.11 0.08 0.09

Si 6.55 6.68 7.07 7.05 7.17 7.28 7.07 7.61 7.60 7.02 7.15

Al 3.25 3.23 3.15 3.18 3.09 2.96 3.12 2.59 2.49 3.21 3.18

Fe 5.20 5.18 4.27 4.43 4.24 4.13 4.39 3.90 3.84 4.43 4.19

Mn 0.23 0.24 0.09 0.11 0.11 0.08 0.11 0.09 0.10 0.09 0.10

Mg 4.43 4.10 4.28 4.18 4.09 3.98 4.05 4.23 4.53 4.24 4.16

Ca 0.14 0.20 0.39 0.32 0.47 0.71 0.53 0.59 0.52 0.32 0.41

Ti 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.00 0.00 0.00 0.01

Sr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Ba 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Tot K+Ca+Na 0.18 0.32 0.60 0.47 0.66 0.92 0.69 0.74 0.68 0.44 0.54

Al Vi 1.45 1.32 0.93 0.95 0.83 0.72 0.93 0.39 0.40 0.98 0.85

Al Vi 1.80 1.92 2.21 2.24 2.27 2.24 2.19 2.20 2.08 2.23 2.33

Tot iv 8.00 8.00 8.00 8.00 8.00 8.00 8.00 8.00 8.00 8.00 8.00

Tot Vi 11.66 11.44 10.86 10.96 10.71 10.42 10.75 10.43 10.56 10.99 10.79

Fe/(Fe + Mg) 0.54 0.56 0.50 0.51 0.51 0.51 0.52 0.48 0.46 0.51 0.50

60

4.3.5 Celadonite


Num 19 24 25 44 45 46 53 54 55 56

Na2O 0.00 0.00 0.00 0.07 0.10 0.05 0.05 0.04 0.06 0.00

K2O 5.34 7.81 7.76 8.44 9.39 6.96 10.09 8.04 9.84 9.91

SiO2 39.36 45.11 45.09 45.82 49.35 42.59 53.06 51.71 52.71 52.74

Al2O3 9.72 8.42 8.86 5.93 6.39 7.37 4.36 5.07 4.18 4.24

FeO 14.69 13.74 13.59 14.23 14.28 15.10 18.36 14.42 19.10 19.00

MnO 0.15 0.15 0.16 0.13 0.00 0.23 0.18 0.00 0.00 0.17

MgO 7.48 5.15 5.09 4.92 4.70 6.20 4.36 3.95 4.39 4.44

CaO 0.60 0.35 0.35 0.19 0.18 0.50 0.44 0.36 0.35 0.35

TiO2 0.11 0.21 0.27 0.43 0.45 0.32 0.57 0.40 0.43 0.41

H2O 22.55 19.08 18.83 19.84 15.16 20.68 8.53 16.02 8.94 8.74

Na 0.00 0.00 0.00 0.01 0.02 0.01 0.01 0.01 0.01 0.00

K 0.61 0.84 0.83 0.93 0.97 0.78 0.99 0.83 0.97 0.97

Si 3.50 3.82 3.80 3.95 4.00 3.73 4.08 4.18 4.07 4.07

Al 1.02 0.84 0.88 0.60 0.61 0.76 0.39 0.48 0.38 0.39

Fe 1.09 0.97 0.96 1.03 0.97 1.11 1.18 0.97 1.23 1.23

Mn 0.01 0.01 0.01 0.01 0.00 0.02 0.01 0.00 0.00 0.01

Mg 0.99 0.65 0.64 0.63 0.57 0.81 0.50 0.48 0.51 0.51

Ca 0.06 0.03 0.03 0.02 0.02 0.05 0.04 0.03 0.03 0.03

Ti 0.01 0.01 0.02 0.03 0.03 0.02 0.03 0.02 0.02 0.02

61

4.4 SEM-EDX

4.4.1 Heu-type zeolites


circle circle 2 circle 3 Circle 5

NUM 1_4 1_1 1_2 2_3 2_4 1b

O 49.12 49.54 48.62 49.45 51.10

Na2O 9.92 1.75 1.25 1.46 1.56 2.41

MgO 0.12

Al2O3 16.67 19.08 17.44 17.99 17.33 17.40

SiO2 71.65 68.37 72.27 72.37 71.65 70.88

K2O 0.08 1.86 1.18 1.43 1.07

CaO 1.56 8.37 7.77 8.09 8.19 5.71

Fe2O3 0.97

wt% heu heu heu heu heu impure Heu?

Na 8.41 1.34 0.94 1.08 1.18 1.85

Mg 0.07

Al 7.63 8.88 7.97 8.14 7.95 8.13

Si 27.81 27.00 28.03 27.79 27.90 28.08

K 0.04 0.93 0.58 0.70 0.53

Ca 0.65 3.54 3.23 3.33 3.42 2.42

Fe 0.29

R 0.78 0.75 0.78 0.77 0.78 0.78

Si/Al 3.65 3.04 3.52 3.41 3.51 3.46

M/M+D 0.92 0.39 0.32 0.35 0.33 0.43

Na/Na+K 1.00 0.59 0.62 0.61 0.69 1.00

E% -22.90 -5.07 -0.11 -3.55 -6.92 25.61

62

4.4.2 Mordenite

Sample 06LM108

Circle circle6 Other

NUM 1_1 1_2 2_1 1_1 1_2

O 50.80 51.11 51.10

Na2O 4.80 4.29 4.99 4.09 3.82

MgO 0.08

Al2O3 15.04 14.30 14.96 16.04 16.29

SiO2 72.52 73.19 71.18 75.23 75.02

K2O 0.13 0.20

CaO 5.29 5.50 5.60 4.51 4.59

Na 4.91 4.39 5.17 4.56 4.26

Mg 0.06

Al 9.35 8.91 9.43 9.64 9.79

Si 38.26 38.67 38.04 38.37 38.27

K 0.08 0.13

Ca 2.99 3.11 3.20 2.46 2.51

Si/Al 4.09 4.34 4.04 3.98 3.91

R 0.80 0.81 0.80 0.80 0.80

M/M+D 0.62 0.59 0.62 0.65 0.63

E% -14.11 -16.11 -18.59 0.73 2.79

Sample 09LM028

Circle circle1 circle 2

NUM 1_1 1_2 1_3 3_1 3_2 5_3 5_4 6_1 7_2 3_3

Na2O 1.01 0.82 1.07 3.32 2.75 2.46 1.20 1.92 1.98 1.85

MgO 0.32 0.53 0.74 0.24 0.07 0.15 0.14 0.15 0.22

Al2O3 15.92 16.86 17.08 16.44 16.77 16.73 17.10 16.81 16.62 14.74

SiO2 77.03 75.73 74.97 75.30 75.76 76.25 76.99 76.68 76.81 79.32

K2O 0.85 0.87 1.06 0.66 0.56 0.63 0.71 0.41 0.51 0.71

CaO 4.88 5.19 5.08 3.75 3.79 3.87 3.85 4.03 3.92 3.15

Fe2O3 0.29 0.36

Na 1.12 0.91 1.19 3.70 3.05 2.72 1.32 2.12 2.19 0.18

Mg 0.24 0.40 0.56 0.18 0.05 0.11 0.11 0.11 0.01

Al 9.50 10.09 10.25 9.87 10.04 9.99 10.17 10.01 9.90 0.78

Si 39.01 38.45 38.18 38.37 38.48 38.64 38.83 38.75 38.83 3.57

K 0.55 0.56 0.69 0.43 0.36 0.41 0.46 0.26 0.33 0.04

Ca 2.65 2.82 2.77 2.05 2.06 2.10 2.08 2.18 2.12 0.15

Fe 0.11 0.14

Si/Al 4.11 3.81 3.72 3.89 3.83 3.87 3.82 3.87 3.92 4.57

R 0.80 0.79 0.79 0.80 0.79 0.79 0.79 0.79 0.80 0.82

M/M+D 0.37 0.31 0.36 0.65 0.62 0.59 0.45 0.51 0.53 0.57

E% 27.62 27.35 19.95 16.30 34.96 34.31 64.85 43.86 41.69 40.61

63

4.4.3 Analcime

Sample 06LM079

circle circle 5 circle 6 circle 9

NUM 1 1c 1_b1 1_b2 1_02

O 47.73 47.73 48.93 48.92 51.84

Na2O 11.67 11.11 11.20 10.88 10.99

Al2O3 21.73 21.35 22.69 21.94 21.03

SiO2 68.71 70.02 65.78 67.20 61.77

Tot 102.12 102.48 99.68 100.01 93.79

Na 11.61 10.96 11.42 11.02 11.94

Al 13.14 12.81 14.07 13.51 13.88

Si 35.25 35.65 34.60 35.11 34.60

R 0.73 0.74 0.71 0.72 0.71

Si/Al 2.68 2.78 2.46 2.60 2.49

E% 13.15 16.85 23.14 22.58 16.31

64

4.4.4 Chlorite/smectite

Sample 06LM079 06LM108 09LM028

Circle circle 3 circle 4 circle 6 circle 1 circle 1

NUM 2_01 2_02 2_05 1_01 1_04 5_03 3_8 1_4 4_6 7_7 7_10

Na2O 0.40 0.46 0.47 0.46 0.98 0.94 2.29 0.29 0.25 0.20

K2O 0.93 0.89 0.80 1.37 2.64 1.26 1.40 0.27 0.41

SiO2 48.11 47.69 50.25 48.20 44.09 43.79 45.88 48.62 44.52 48.21 51.92

Al2O3 11.94 12.24 12.45 10.88 15.47 15.23 17.85 19.08 18.69 14.72 21.99

FeO 23.59 24.56 25.04 25.41 23.17 21.06 18.55 15.17 17.79 15.78 7.23

MgO 9.52 8.61 9.19 9.75 10.73 10.12 12.34 14.22 18.17 1.91 2.39

CaO 4.31 4.95 4.53 4.77 1.61 1.83 1.82 1.22 0.83 18.85 15.87

H2O 1.20 0.60 -2.72 0.53 2.57 4.40 0.01 0.01 -0.01

Tot 98.80 99.40 102.72 99.47 97.43 95.60 99.99 100.00 100.00 99.99 100.01

Na 0.14 0.16 0.16 0.16 0.34 0.33 0.77 0.09 0.09 0.06

K 0.21 0.20 0.17 0.32 0.62 0.28 0.30 0.06 0.09

Si 8.59 8.52 8.63 8.60 7.99 8.08 7.92 8.14 7.56 8.48 8.56

Al 2.51 2.58 2.52 2.29 3.31 3.31 3.63 3.76 3.74 3.05 4.27

Fe 3.52 3.67 3.60 3.79 3.51 3.25 2.68 2.12 2.53 2.32 1.00

Mg 2.53 2.29 2.35 2.59 2.90 2.78 3.18 3.55 4.60 0.50 0.59

Ca 0.82 0.95 0.83 0.91 0.31 0.36 0.34 0.22 0.15 3.55 2.80

K+Ca+Na 1.17 1.31 1.17 1.07 0.97 1.32 1.38 0.61 0.15 3.70 2.95

AlVi -0.59 -0.52 -0.63 -0.60 0.01 -0.08 0.08 -0.14 0.44 -0.48 -0.56

AlVi 3.10 3.10 3.16 2.88 3.30 3.39 3.55 3.90 3.30 3.54 4.84

Tot iv 8 8 8 8 8 8 8 8 8 8 8

Tot Vi 9.16 9.06 9.11 9.27 9.71 9.42 9.41 9.57 10.42 6.36 6.42

z>y 0.74 0.74 0.74 0.75 0.79 0.77 0.78 0.77 0.84 0.59 0.59

z<y 0.90 0.91 0.89 0.91 0.87 0.88 0.86 0.83 0.86 1.24 1.02

Fe/Fe+mg 0.58 0.62 0.60 0.59 0.55 0.54 0.46 0.37 0.35 0.82 0.63

65

4.4.5 Plagioclase

1.


circle circle 1 circle 4 circle 9 circle 1 circle 2

NUM 1d 1_02 2_01 2_02 1_1 1_2 3_7 3_9 1_1 1_2 2_1

O 45.55 44.89 45.38 45.14 52.79 51.84

Na2O 9.99 10.27 10.86 5.70 8.12 10.99 10.01 10.81 4.10 4.11 3.65

Al2O3 22.92 21.33 21.62 27.66 20.85 21.03 17.14 19.46 32.33 32.03 32.58

SiO2 70.70 74.02 75.15 60.07 58.78 61.77 72.22 68.62 50.10 50.20 49.57

K2O 1.51 1.93 0.34 13.47 13.67

CaO 0.87 11.08 3.75 0.62 14.19

MgO 0.29 0.49

Tot 105.99 107.55 107.63 104.52 91.51 93.79 100.00 100.00 100.00 100.01 99.99

Na 0.80 0.81 0.85 0.47 0.76 0.99 0.94 1.02 0.42 0.42 0.36

Al 1.12 1.02 1.02 1.40 1.18 1.16 0.87 0.99 1.79 1.77 1.75

Si 2.92 3.01 3.02 2.58 2.83 2.88 3.10 2.97 2.35 2.36 2.25

K 0.08 0.10 0.02 0.81 0.82

Ca 0.04 0.51 0.19 0.03 0.69

Mg 0.02 0.03

R 0.72 0.75 0.75 0.65 0.71 0.71 0.78 0.75 0.57 0.57 0.56

Si/Al 2.62 2.94 2.95 1.84 2.39 2.49 3.58 2.99 1.31 1.33 1.29

Si+Al 4.04 4.03 4.04 3.98 4.01 4.04 3.97 3.96 4.14 4.13 4.00

Ca 0.04 0.00 0.00 0.52 0.20 0.00 0.00 0.03 0.00 0.00 0.66

Na 0.87 0.89 1.00 0.48 0.80 1.00 0.98 0.97 0.34 0.34 0.34

K 0.09 0.11 0.00 0.00 0.00 0.00 0.02 0.00 0.66 0.66 0.00

Type alb alb alb lab oli alb Alb alb san san lab

66

2.

Sample 06LM108

Circle circle 3 circle 6 circle 7

NUM 3_1_1 3_1_2 3_2_1 3_2_2 6_003_01 7_001_03 7_001_04 7_001_05

O 50.61 44.23 45.26 45.43

Na2O 3.43 2.77 3.43 3.96 3.26 4.92 10.93 10.20

Al2O3 32.34 33.07 19.44 20.93 20.07 30.61 20.86 19.22

SiO2 49.89 49.91 69.50 67.17 66.28 54.02 73.81 77.36

K2O 0.20 0.26 1.25 0.87

CaO 13.99 13.82 6.20 6.95 7.51 14.92 1.53 0.43

MgO 0.15 0.16 0.18 0.12 0.60

Tot 100.00 99.99 100.00 100.00 97.12 104.46 107.12 107.81

Na 0.34 0.27 0.32 0.38 0.28 0.42 0.86 0.79

Al 1.73 1.77 0.99 1.07 1.06 1.58 1.00 0.91

Si 2.27 2.26 3.01 2.92 2.96 2.36 3.00 3.10

K 0.01 0.02 0.07 0.05

Ca 0.68 0.67 0.29 0.32 0.36 0.70 0.07 0.02

Mg 0.01 0.01 0.01 0.01 0.00 0.04

R 0.57 0.56 0.75 0.73 0.74 0.60 0.75 0.77

Si/Al 1.31 1.28 3.03 2.72 2.80 1.50 3.00 3.42

Si+Al 4.00 4.03 4.00 4.00 4.01 3.94 4.00 4.00

Ca 0.66 0.70 0.42 0.43 0.56 0.63 0.07 0.02

Na 0.33 0.29 0.48 0.50 0.44 0.37 0.93 0.98

K 0.01 0.02 0.10 0.06 0.00 0.00 0.00 0.00

Type lab byt and and lab lab alb alb

67

3.

Sample 09LM028

circle circle 1 circle 2

NUM 4_1 4_2 4_5 5_1 5_2 5_5 2_4 2_5 2_6 4_2

Na2O 3.28 10.53 9.84 0.55 3.31 1.08 0.22 2.15 2.48 2.73

Al2O3 32.57 22.51 22.59 20.39 33.02 37.32 24.15 20.86 32.30 31.39

SiO2 52.42 64.62 64.83 71.02 52.20 52.87 53.11 69.82 52.79 54.10

K2O 0.16 0.09 0.69 1.56 0.22 7.95 0.21 1.13 1.26 1.80

CaO 10.97 2.02 2.05 6.25 11.15 0.47 19.66 5.71 10.95 9.92

MgO 0.13 0.24 0.24 0.11 0.31 2.65 0.34 0.22 0.06

Tot 99.53 100.01 100.00 100.01 100.01 100.00 100.00 100.01 100.00 100.00

Na 0.32 1.01 0.94 0.05 0.32 0.11 0.02 0.24 0.26 0.29

Al 1.72 1.16 1.16 1.03 1.74 1.97 1.34 1.25 1.85 1.80

Si 2.36 2.82 2.83 3.04 2.34 2.36 2.50 3.55 2.56 2.63

K 0.01 0.01 0.04 0.09 0.01 0.45 0.01 0.07 0.08 0.11

Ca 0.53 0.09 0.10 0.29 0.53 0.02 0.99 0.31 0.57 0.52

Mg 0.01 0.02 0.02 0.01 0.02 0.19 0.03 0.02

R 0.58 0.71 0.71 0.75 0.57 0.55 0.65 0.74 0.58 0.59

Si/Al 1.37 2.44 2.44 2.96 1.34 1.20 1.87 2.84 1.39 1.46

Si+Al 4.08 3.98 4.00 4.07 4.08 4.33 3.84 4.79 4.41 4.43

Ca 0.61 0.09 0.09 0.68 0.61 0.04 0.97 0.50 0.63 0.56

Na 0.37 0.91 0.87 0.12 0.37 0.18 0.02 0.38 0.29 0.32

K 0.01 0.00 0.04 0.20 0.01 0.78 0.01 0.12 0.09 0.12

Type lab alb alb ? lab san ano lab byt lab

68

4.


circle circle 1 circle 2 Circle 2 circle 4

NUM 1_1 1_2 2_1 2_2 2_3 2_4 1_01 1_02 1_01 1_02

O 46.58 41.89 46.65 46.47

Na2O 22.09 22.76 15.78 15.73 12.48 21.02 0.82 11.07 1.01 0.86

Al2O3 17.97 12.67 20.38 20.82 16.29 15.15 24.98 23.16 24.05 24.37

SiO2 59.10 62.05 63.47 62.91 69.25 62.35 62.32 80.50 62.87 63.39

K2O 0.29 0.50 0.16 0.21 0.51 0.27 1.34 2.36 2.71

CaO 0.49 2.02 0.06 0.23 1.33 1.21 12.44 11.92 11.33

MgO 0.05 0.15 0.10 0.15 0.76

Tot 99.99 100.00 100.00 100.00 100.01 100.00 102.66 114.73 102.22 102.67

Na 2.21 2.29 1.53 1.52 1.19 2.09 0.07 0.81 0.09 0.07

Al 0.97 0.69 1.06 1.09 0.84 0.81 1.27 1.03 1.24 1.25

Si 2.70 2.86 2.81 2.79 3.03 2.84 2.70 3.03 2.74 2.75

K 0.02 0.03 0.01 0.01 0.03 0.02 0.07 0.13 0.15

Ca 0.02 0.10 0.00 0.01 0.06 0.06 0.58 0.56 0.53

Mg 0.01 0.01 0.01 0.05

R 0.74 0.81 0.73 0.72 0.78 0.78 0.68 0.75 0.69 0.69

Si/Al 2.79 4.16 2.64 2.56 3.61 3.49 2.12 2.95 2.22 2.21

Si+Al 3.67 3.54 3.88 3.88 3.87 3.65 3.97 4.05 3.98 3.99

Ca 0.01 0.04 0.00 0.01 0.05 0.03 0.80 0.72 0.70

Na 0.98 0.95 0.99 0.99 0.93 0.97 0.10 0.17 0.20

K 0.01 0.01 0.01 0.01 0.02 0.01 0.10 1.00 0.11 0.10

Type alb alb alb alb alb alb Byt alb byt byt

69

4.4.6 Pyroxene


circle circle 9 circle 3 circle 4

NUM 2 1_02 1_03 1_01

O 42.04 40.37 39.22 40.40

Na2O 1.21 2.47 2.52 1.54

Al2O3 1.86 1.40 1.81 1.42

SiO2 52.70 53.44 55.79 55.73

K2O 0.00 0.34 0.00 0.00

CaO 18.21 22.00 21.52 22.21

Fe2O3 18.75 14.90 15.18 14.13

MgO 8.82 9.37 9.75 9.78

Total 101.53 103.90 106.58 104.80

Na 0.09 0.18 0.18 0.11

Al 0.08 0.06 0.08 0.06

Si 2.02 2.00 2.01 2.03

K 0.00 0.02 0.00 0.00

Ca 0.75 0.88 0.83 0.87

Fe 0.54 0.42 0.41 0.39

Mg 0.50 0.52 0.52 0.53

R 1.08 0.97 0.96 0.97

Si/Al 24.09 32.43 26.10 33.37

Ca 0.42 0.48 0.47 0.49

Mg 0.28 0.29 0.30 0.30

Fe 0.30 0.23 0.23 0.22

Type aug dio dio Dio

70

4.5 ICP-OES

Major and minor elements

wt% SiO2 Al2O3 Fe2O3 MgO CaO BaO SrO K2O Na2O MnO TiO2 P2O5 TOT TOFe0 H2O-

CO2

09LM060 57.24 15.30 6.79 2.04 5.72 0.20 0.07 1.20 2.44 0.08 0.43 0.13 91.69 91.01 8.99

09LM059 65.12 10.77 3.75 1.49 6.39 0.24 0.07 1.59 2.01 0.05 0.25 0.15 91.97 91.60 8.40

09LM058F 64.62 7.75 3.69 1.37 8.45 0.08 0.04 0.96 0.93 0.06 0.25 0.14 88.40 88.03 11.97

09LM058 58.15 9.40 2.53 0.66 11.11 0.09 0.02 0.37 1.88 0.07 0.30 0.09 84.71 84.46 15.54

09LM057 57.48 13.22 6.49 1.15 6.67 0.14 0.05 0.58 2.39 0.10 0.55 0.13 88.99 88.34 11.66

09LM056 62.74 10.96 2.52 0.80 7.46 0.10 0.05 1.21 1.85 0.06 0.27 0.10 88.18 87.93 12.07

09LM055 57.53 13.83 7.90 2.57 5.37 0.08 0.03 1.27 2.39 0.11 0.51 0.15 91.79 90.99 9.01

09LM054 62.66 13.23 5.53 1.88 4.36 0.11 0.06 1.55 2.21 0.12 0.37 0.12 92.24 91.69 8.31

09LM053 57.12 14.01 6.71 2.47 5.61 0.11 0.04 1.69 2.05 0.11 0.41 0.14 90.54 89.87 10.13

09LM052 54.87 16.47 6.20 1.65 7.88 0.10 0.04 0.71 2.97 0.11 0.37 0.15 91.54 90.92 9.08

09LM051 61.19 6.64 2.42 0.89 13.19 0.08 0.03 0.96 0.75 0.06 0.23 0.08 86.57 86.33 13.67

09LM042 66.20 14.55 7.86 2.47 4.69 0.11 0.03 1.45 2.24 0.13 0.55 0.14 100.48 99.69 0.31

09LM041 68.79 7.92 2.67 0.90 7.10 0.04 0.02 0.72 1.40 0.07 0.27 0.08 90.06 89.80 10.20

09LM040 69.10 8.55 3.80 1.41 14.24 0.10 0.04 1.42 1.41 0.12 0.25 0.10 100.59 100.21 0.00

09LM039 78.55 15.26 5.03 1.48 5.16 0.36 0.08 1.02 2.26 0.08 0.37 0.13 109.86 109.35 0.00

06LM116 65.65 11.87 4.90 1.41 3.54 0.04 0.01 0.52 2.92 0.11 0.37 0.31 91.72 91.23 8.77

09LM038 64.80 12.09 5.38 1.76 3.92 0.05 0.02 1.03 2.42 0.12 0.38 0.23 92.28 91.74 8.26

06LM115 62.67 12.39 6.71 2.36 3.72 0.03 0.02 1.05 2.53 0.14 0.41 0.13 92.21 91.54 8.46

09LM036 58.63 13.10 7.80 3.28 4.48 0.08 0.05 1.16 1.96 0.16 0.45 0.10 91.30 90.51 9.49

09LM035 65.12 16.21 10.73 3.97 6.44 0.01 0.00 0.52 3.31 0.17 0.64 0.12 107.31 106.23 0.00

06LM108 61.09 14.79 5.85 2.29 5.45 0.06 0.04 1.27 2.22 0.13 0.34 0.25 93.88 93.30 6.70

09LM028 62.81 14.47 5.69 2.11 6.67 0.06 0.04 1.21 2.20 0.10 0.32 1.62 97.60 97.03 2.97

09LM027 58.47 15.58 6.77 2.89 5.89 0.01 0.00 0.47 3.31 0.12 0.33 0.09 93.98 93.30 6.70

09LM026 70.78 11.90 1.78 0.60 3.56 0.09 0.05 1.07 2.14 0.04 0.22 0.07 92.32 92.14 7.86

09LM025 68.27 13.12 2.45 0.88 3.82 0.07 0.07 1.13 2.49 0.09 0.23 0.10 92.75 92.51 7.49

09LM024 65.77 12.94 6.02 1.37 3.41 0.19 0.07 1.38 3.22 0.11 0.40 0.13 95.05 94.45 5.55

71

Trace elements

ppm Cd Co Cr Cu La Ni Rb Sc V Y Zr

09LM060 b.d. b.d. 27.69 73.85 9.23 b.d. 30.58 13.85 55.39 23.08 36.93

09LM059 b.d. b.d. 73.40 0.00 39.15 9.79 109.14 9.79 58.72 29.36 371.91

09LM058F b.d. b.d. 14.44 86.65 115.54 b.d. 9.69 14.44 67.40 14.44 38.51

09LM058 b.d. b.d. 52.65 57.44 14.36 b.d. 1.29 23.93 234.54 14.36 28.72

09LM057 b.d. b.d. 19.20 48.00 4.80 4.80 29.50 14.40 57.60 14.40 38.40

09LM056 b.d. b.d. 29.80 79.45 9.93 b.d. 16.45 29.80 203.60 14.90 29.80

09LM055 b.d. b.d. 19.24 57.71 28.86 b.d. 13.12 19.24 110.62 19.24 33.67

09LM054 b.d. b.d. 24.76 79.22 14.85 b.d. 18.39 24.76 168.34 14.85 34.66

09LM053 b.d. b.d. 28.97 53.11 9.66 14.48 8.63 28.97 173.80 14.48 19.31

09LM052 b.d. b.d. 23.89 52.55 4.78 b.d. 23.48 9.56 23.89 14.33 47.78

09LM051 b.d. b.d. 14.72 44.17 9.82 b.d. 25.29 29.45 152.14 19.63 44.17

09LM042 b.d. b.d. 19.26 38.51 139.61 b.d. 16.52 14.44 38.51 19.26 43.33

09LM041 b.d. b.d. 71.73 0.00 38.26 b.d. 105.02 9.56 57.39 23.91 363.44

09LM040 b.d. b.d. 41.96 51.29 18.65 13.99 33.73 13.99 60.61 23.31 55.95

09LM039 b.d. b.d. 71.26 47.51 9.50 23.75 28.09 19.00 76.01 23.75 52.26

06LM116 b.d. b.d. 29.19 48.65 9.73 b.d. 15.45 24.33 180.01 14.60 34.06

09LM038 b.d. b.d. 14.60 48.65 9.73 b.d. 20.29 24.33 92.44 19.46 38.92

06LM115 b.d. b.d. 19.16 81.45 9.58 b.d. 24.23 14.37 86.24 14.37 38.33

09LM036 b.d. b.d. 24.66 49.32 4.93 b.d. 17.86 29.59 123.30 19.73 39.45

09LM035 b.d. b.d. 39.15 88.08 9.79 24.47 15.53 44.04 225.10 19.57 39.15

06LM108 b.d. b.d. 14.74 44.21 9.83 b.d. 10.49 29.48 117.90 19.65 34.39

09LM028 b.d. b.d. 14.96 29.91 4.99 b.d. 0.00 19.94 64.81 24.93 44.87

09LM027 b.d. b.d. 19.71 34.49 4.93 b.d. 9.72 29.56 133.03 14.78 29.56

09LM026 b.d. b.d. 23.08 32.31 0.00 9.23 24.07 13.85 32.31 18.46 73.85

09LM025 b.d. b.d. 19.29 33.76 4.82 b.d. 23.95 14.47 48.23 14.47 43.41

09LM024 b.d. b.d. 34.80 39.77 9.94 14.91 22.53 19.88 164.03 9.94 24.85

72

Appendix 5 – Terrain observations and petrographical analyses of the samples of the Río Guaraguao section

73

5.1 The Piñón and Calentura Formations

5.1.1 The Piñón Formation

The Piñón Formation crops out north of the

study area in the mountainous region named

“Cerro Azul” or blue hill, referring to the

greenish blue colour of massive basalts of the

Piñón Formation. Massive volcanic rocks can

be observed in fresh outcrops along the road

towards Isidro Ayora. Pillow lavas are

observed along the same road and in the quarry

near the village Las Mercedes. Pillow lavas are

brown in colour because of intensive

weathering to clay minerals.

The contact of the Piñón Formation with lapilli

tuffs can be observed in a road cut west of the

Guaraguao section (Sample 04LM095, figure

4.2). At this location the Piñón Formation

consists of dark green volcanics, is strongly

magnetic and intensely veined with quartz. A

conform contact with incompetent brown

lapilli tuffs is observed at this location. The

sample of the Piñón Formation is composed of

plagioclase laths, euhedral to anhedral Fe-Ti

oxides in a fine matrix of mosaic crystals. No

pyroxenes are observed, but these are probably

replaced by alteration minerals.

In the Río Guaraguao, typical green massive

basalts were observed at the top of the Piñón

Formation (Sample 09LM072). The Río

Guaraguao runs parallel to the contact of the

Piñón and Calentura Formation at this location.

The contact can not be seen in outcrop, but is

inferred from a change in soils and vegetation,

as pillow lavas of the Piñón Formation are

typically weathered to dark brown greywackes

and brown clayey soils. The sample of the

Piñón Formation is composed of large euhedral

plagioclase laths with carlsbad twins,

clinopyroxenes and Fe-Ti oxides.

5.1.2 The Calentura Formation

The major part of the Calentura Formation

consists of fine-grained (silt to sub-silt)

competent light grey to black beds of 10 to 30

centimetres in thickness (e.g. 06LM011).

Hundreds of these beds are exposed in a high

section at GPS 09–101. Weathering causes a

white porous outlook in outcrop. Some beds

are black in colour (Sample 06M001), because

of a high organic content. Most beds are very

competent because of high silicification. In

sample 04LM001, Inoceramus shells can be

found in life position. Some beds are

homogeneous, while others have a fine

undulose lamination (grey-brown-black).

Sample 06LM011 is composed of

homogeneous submicroscopic matrix.

Foraminifera occurs spread through the matrix.

Crystal clasts occur, but are rare. Sample

06LM012 is similar in composition, but

contains more clays.

Some thin (smaller than 20 cm) fine lapilli tuff

beds and clay beds (smaller than 20 cm) are

present near the top of the Calentura

Formation (Samples 06LM12–14). These beds

are incompetent, iron brown in colour, with

some large green irregular argillized glass

remains present. Other lapilli tuffs are

composed of black and white clasts in a white

matrix. Sample 06LM013 is composed of

feldspar crystal clasts, minor augite crystal

clasts and some volcanic particles. A large

amount of laminated particles, which are

completely replaced by a brown clay, occur.

These particles were possibly originally

pumice, which were strongly compacted

between the more competent crystal clasts. No

remaining vesicles can be observed.

APPENDIX 5 - TERRAIN OBSERVATIONS AND PETROGROPHICAL ANALYSES OF THE VOLCANIC COMPONENTS, STRUCTURES AND TEXTURES OF THE SAMPLES OF THE RÍO GUARAGUAO SECTION


74

Sample 06LM014 is composed of undulose

laminae rich in microorganisms, crystal clasts

(mainly rounded to angular plagioclase and

some quartz) and possibly some blocky glass

fragments. The different types of clasts occur

together, are moderately well sorted and some

laminae are concentrated in microorganisms or

crystal clasts.

Higher in the section, 20 to 30 centimetre thick

incompetent brown clayey layers alternate with

more competent beds (GPS 06–009). The

competent beds are dark grey to black in

colour and have a fine undulose lamination or

black nodules occur parallel to the lamination.

At this point, 200 meters of the section is

unexposed. It is suggested that this part mainly

consists of easily weathered layers, which alter

to brownish clays which can not be seen in

outcrop.

5.2 The lower unit of the Cayo Formation (Río Guaraguao unit)

5.2.1 Coarse breccia at the base of the

Cayo Formation

In the Río Guaraguao, the base of the

Calentura/Cayo Formation is faulted by NNE–

SSW oriented transform and/or thrust faults.

At the base intensely silicified light brown

cherts and fine breccias occur. Because the

river follows the contact, these rocks are

observed at different locations (Samples

09LM073–074, GPS09–85–86). At location

09LM077 black lavas are in conform contact

with brown cherts and breccias, composed

mainly of crystal clasts.

Apart from the cherts and fine-grained breccias

occurring at the contact with the Piñón

Formation, the basal part of the Cayo

Formation is composed of competent well

cemented coarse breccia sequences. No contact

with the first breccia sequence and underlying

strata could be observed in outcrop.

Northern unit of breccia

A first sequence was observed near the contact

with the Piñón Formation (Samples 09LM075–

076). It consists of large clasts of 10 to 50

centimetres in size with a greyish or green

colour, which appear porphyritic volcanics.

Similar, more angular finer grained clasts are

embedded in a greyish microcrystalline matrix,

which is similar in appearance as the rock

fragments. At several locations, greenish and

white microcrystalline alteration/vein zones

penetrate between clasts and alter the matrix

and finer grained clasts. Similar outcrops of

coarse breccia are observed higher in the

sequence, but because no continuous outcrop is

exposed, it can not be deduced if they belong

to the same sequence or to multiple sequences

(Samples 09LM070–71, GPS 09–88–94 and

GPS 97–100). When different outcrops are

compared, a grading of clasts is observed,

which it is an argument for the presence of

multiple sequences.

It could not be deduced if sequences are

coarsening or fining upwards. The matrix of

the breccia is observed in sample 09LM078.

The matrix contains lapilli clasts of different

types of porphyritic volcanics, and mainly

angular fractured plagioclase crystal clasts.

These are embedded in a fine-grained mosaic

of feldspar and quartz. No remains of pumice

are visible. Two meter large blocks of greenish

aphanitic volcanics of the Piñón Formation are

present in samples 09LM070–71.

At GPS 09–095–96, the upper part of a coarse

breccias sequence is in conform contact with a

unit of fine-grained siltstones. The unit is 5

meters thick, individual beds are 10 to 30

centimetres thick and have undulose bedding.

The outer part of the rocks is greyish-white

when weathered, which gives the appearance

of limestones to the rocks. On fresh cuts, the

rocks are light grey to black in colour, are

highly silicified and have a carbonate and

organic material content. Large nodules, up to

five centimetres in size, occur, contain iron

oxides, but were probably originally pyrite.

Black structures are interpreted as

bioturbations. It can not be observed in outcrop

which rocks are exposed above these

sequences and it is thus not known if coarse

breccia where deposited above this point.

A second contact of coarse breccias with fine-

grained sequences is observed at location GPS

09–100. At this location, the uppermost part of

a sequence of coarse breccia, at this location

fining upwards (GPS 09–97–100), is overlain


75

by an 80 centimetre thick layer of greyish-

green compacted lapilli tuffs (Sample

09LM081). These lapilli tuffs consist of

rounded clasts embedded in a fine matrix.

When weathered, the clasts give an undulose,

“mottled” appearance to the rocks. Because of

their characteristic appearance, this lithology

will further be called “grey mottled lapilli

tuffs”. At this location, the unit is intensely

veined. The sample is composed of different

types of porphyritic andesitic volcanic clasts

and crystal fragments of clinopyroxene,

plagioclase, Fe-Ti oxides and some

amphiboles. Some clasts are entirely replaced

by a brown clay mineral. They contain large

phenocrysts of plagioclase. These clasts are

strongly compacted and indented by the harder

volcanic clasts around and no vesicles are

visible. These clasts possibly represent

compacted pumice.

The grey mottled lapilli tuffs are covered by

two meters of claystones, which are composed

of alternating beds of 10 to 30 centimetres

thick clay-rich incompetent and hard silicified

rocks. The clayey rocks are greenish in colour

and contain nodules of pyrite, oxidized by

weathering. On top of this, a 40 centimetre

thick chert horizon occurs, which underlays a

thick sequence of lapilli tuffs. These lapilli

tuffs defer from the coarse breccia observed

below, because they are iron brown,

incompetent, have a smaller clast size (up to 5

cm) and show typical onion weathering

structures.

Southern unit of breccia

At GPS 006–004,005,010 a several meter thick

breccia occurs. It is similar in appearance as

the breccias observed in the northern unit

although clasts may be more rounded and in

some outcrops a larger amount of matrix is

present. A noted difference is the occurrence of

red rounded clasts and the absence of basalt

clasts. Both clasts and matrix are very

competent, light-grey to yellow-grey in colour

(Sample 06LM004), lighter than the matrix

and clasts range from centimetre to larger than

50 centimetres in size (06LM002) and contain

two grain-size populations (between 3 to 5 cm

and larger than 30 cm). Samples 06LM003 and

06LM004 consists for the major part of a fine

cryptocrystalline matrix. Euhedral pyroxene,

amphibole, plagioclase and Fe-Ti oxides

phenocrysts occur. Some phenocrysts are

completely altered. Because of the high degree

of alteration, it is difficult to see if these

samples were originally composed of multiple

clasts, which were cemented together or if the

sample is a volcanic rock with a

cryptocrystalline matrix and phenocrysts.

The red colour of some clasts of the coarse

breccia is noted also in the fine beds above the

breccia. Light purple to pink homogeneous

porous siltstones are observed. They are

interbedded with fine lapilli tuffs with white

clasts (feldspars?) in a white to purple matrix

(Samples 06LM05–010). These layers are

strongly faulted and tilted, and because no

contact with the breccias can be observed, it is

not sure that they stratigraphically overlay the

breccias. At location GPS 09–102, red beds are

interstratified with incompetent brownish

claystones and silicified beds of up to 30

centimetres thick. The claystones are iron

brown and very incompetent. The silicified

rocks are black and very competent. Beds have

an undulous lamination and contain dark grey

to black nodules parallel to lamination.

Above these fine beds a new coarse breccia

unit occurs, similar in appearance as the

breccia unit below. Next to grey porphyritic

volcanics, greenish and reddish clasts occur.

Microcrystalline quartz veins and amygdules

up to 15 centimetres in size occur in the

matrix. These breccia layer is overlain by a 4

meter thick layer of “grey mottled lapilli tuffs”,

similar in appearance as the ones observed in

GPS 09–100. This lithology is built up of

different grey, rounded and slightly flattened

clasts, which are cemented together into a

competent rock. These clasts have a

homogeneous size of two to five centimetres,

although it can change gradually through the

unit. The erosion of some of the matrix around

the clasts at the surface is responsible for the

ondulating “mottled” appearance of the rocks.

Sample 09LM085 is composed of rounded

andesitic volcanic fragments and plagioclase,

feldspar, Fe-Ti oxides and quartz crystal clasts.

Laminated, compacted and indented clay-rich

particles were probably strongly compacted

pumice. No remaining vesicles are visible.

Some larger accessory well rounded clasts

occur in the grey mottled lapilli tuffs, which


76

can be up to one meter large. Three different

types can be distinguished. A green competent

rock, resembling the parent lithology, grey-

yellowish clasts (probably the same material as

in the coarse breccias) and red homogeneous

fine-grained rocks (silt to sub-siltsize).

On top of this unit a 30 centimetre thick,

red/green chert unit occurs, similar in

appearance as the red clasts occurring in the

underlying lithologies (06LM098). Above this,

two coarse breccia units occur, with clasts up

to 40 centimetres in size. The sequence is

fining upwards and terminates in a black

laminated siltstone, which grades into a

greenish tuff. Above this point, no coarse

breccia are observed.

5.2.2 The basal part of the lower

unit

The depositional sequences above are typically

of metre thickness. They can have the same

appearance as the grey mottled lapilli tuffs

described in the beds below (e.g. 06LM102),

though the majority of the beds is less

competent and have a typical brownish onion

weathering surface. Clasts are of centimetre

size, fresh cuts are greenish in colour

(06LM100, 09LM086-087) and accessory red

rounded chert clasts, up to one metre in size,

are present. Sample 06LM102 is highly

altered, which makes it difficult to identify any

primary structures. It contains angular crystal

clasts (feldspar, quartz, augite, amphibole, Fe-

Ti oxides), other particles could be strongly

altered glass shards. Sample 09LM086 is

composed mainly of crystal clasts (plagioclase,

augite) and different types of volcanic

particles. Probably some glass shards and

pumice were present. The high concentration

of crystal clasts and volcanic fragments and the

rounding of the clasts shows that the rock

could be epiclastic.

Finer grained greenish lapilli tuff beds,

containing compacted pumice clasts, are

interbedded (06LM101). This sample is

composed mainly of tubular pumice, which is

moderately compacted. Next to pumice,

elongated shards, which results from the same

pumices are present. Crystals clasts are mainly

plagioclase. The sequences are alternated with

black or reddish to green fine-grained rocks.

The red beds are similar in appearance as the

red clasts occurring in the lapilli tuff

sequences.

Higher in the sequence the “mottled”

appearance of lapilli tuffs disappears. Lapilli

tuff sequences are densely compacted

(06LM102, 09LM88, 09LM001), fining

upwards and are generally not thicker than a

metre. They are reddish green to white in

colour. Sample 09LM088 is composed mainly

of tubular pumice, contains some andesitic

volcanic fragments and large quartz, alkali-

feldspar and plagioclase phenocrysts. Sample

09LM001 is highly altered, some ghost suggest

a possible original pumiceous composition.

Crystal clasts are alkali feldspars, plagioclase

and Fe-Ti oxides.

The lapilli tuff sequences are intercalated with

multiple 20-30 cm thick bluish green hard and

brown porous tuff layers (06LM10, 09LM89).

These tuff layer horizons can be correlated

over large distances and when several metres

thick, they are exploited for their zeolite

content. Several small quarries exits west of

the section along the Casas Viejas – Isidro

Ayura road (e.g. 04LM009) and north of

Guayaquil (04LM015).

Tuffs of the lower unit of the Cayo Formation

are typically intensely light green to beige or

have a flaser bedding structure of red and

green. Some tuffs are silicified, hard and

dense, while others are light weighted, have a

concoidal fracture and absorb water easily.

Another characteristic is their homogeneity,

they possess no internal lamination.

5.2.3 The middle part of the lower

unit

The middle part of the lower unit of the Cayo

Formation is dominated by metre to decametre

size sequences of coarse green lapilli tuffs. The

sequences typically have a flat base, can

coarsen upwards, are massive and compacted

at the base, are composed of spherical particles

of two to six centimetres in size in the middle

part and can be layered near the top. The top is

generally finer, denser, well cemented and less

porous than the base.


77

The particles occurring in the middle part of

the sequences, can be round in form or have a

triangular form with a convex lower surface

and a rounded upper surface, or alternatively

the lower surface is flat and the upper surface

convex. They are composed of several tubular

pumice clasts and sometimes volcanic rock

fragments, which are embedded in a matrix of

finer pumice or pumice shards. It is not clear if

these particles are clasts or if they were formed

by later fracturation or alteration.

Vilema (pers. com., 2006) introduced the term

“almeja”, the Spanish word used for shells, to

describe the structures of the clasts. When

weathered, almeja sequences are similar in

appearance as the grey mottled lapilli tuffs.

Therefore the informal terms “green mottled

lapilli tuffs” or “almejas sequences” will

further be used to describe the sequences and

the term “almejas” will be used to describe the

particles. These “almeja” sequences are very

characteristic for the lower unit of the Cayo

Formation, and can be found in the entire

region from Guayaquil through the Cordillera

Chongón-Colonche and parts of the Cordillera

Costera.

At this part of the section some sequences were

studied in detail to get a better understanding

of the origin of these deposits.

Section 1 of the lower unit of the Cayo

Formation

This section is 25 metres thick and contains the

lowermost “almeja” unit observed in the Río

Guaraguao section, although Vilema (2008)

observes almejas lower in the section.

A black competent siltstone (09LM002) and 20

centimetres of brown clays underlay three

metres of bluish green almejas (09LM003),

which are covered by a metre of five to ten

centimetre thick beds of tuffs. Veins cut trough

the basal part of the almejas and through the

underlying strata. The almejas are composed of

large particles of compacted tubular pumice

embedded in a matrix of smaller glass, crystal

and pumice clasts. Vesicles are bent off around

phenocrysts in the pumice. Glass shards are

angular, blocky to irregular and show no

vesicle wall remains. Crystal clasts are mainly

quartz and alkali feldspars.

Above this first almeja unit, hard and

competent metre thick lapilli tuffs with

compaction structures occur (09LM005). They

fill up deeply incised erosive gullies.

Sequences are clearly fining upwards and

grade into thin beds, which are deposited

parallel to the gully incisions. The rocks are

grey in outcrop, but bluish to white in fresh

cuts. The lapilli tuffs are similar in particle

composition as the almeja sequence below, but

pumice clasts are somewhat smaller. The

sample contains some volcanic fragments and

quite a lot of angular fractured quartz and

feldspar crystal clasts. The sequences are

covered by oxidized brown clays (0.5 m) and

by one and a half metres of 10 to 15 centimetre

thick green tuff beds (09LM006) and a second

similar thinner lapilli tuff sequence. White

veins are visible in and around the clay bed.

The tuff beds grade into light grey siltstones

(09LM007-008,06LM104) which underlay

three metre thick incompetent fine brown

lapilli tuffs (09LM009-011). The lapilli tuffs

are composed of pumice and different kinds of

volcanic clasts of three to four centimetres in

size and accessory large red and brown

rounded clasts (up to 0.5 m). The sequence is

coarsening upwards and becomes also more

competent upwards. Sample 09LM009 is

composed of volcanic clasts and pumice.

Pumice is somewhat different from the pumice

below, it has larger vesicles, with both tubular

and larger round vesicles with thicker walls

occurring. Other pumice has a lot of

plagioclase phenocrysts, or a microlitic matrix.

This material was possibly already crystallized

before eruption and is named “schlacke”.

Perlitic volcanic particles are also quite

common. Volcanic particles are microlitic or

contain spherulitic structures. Crystal clasts are

fractured alkali feldspar, augite, plagioclase

and quartz. Some splintery glass shards occur

in the matrix. Sample 09LM011 is similar to

sample 09LM009. It contains a high amount of

vesiculated perlites. Some volcanic particles

with a mosaic structure occur.

The next layer, has an irregular contact at the

base and is composed mainly of pumice,

contains no lithoclasts and is fining upwards.

Near the top, centimetre size holes occur which

have a long axis aligned along layering. This

sequence is topped by a second “almeja” unit


78

of several metres thick (06LM106). Red fine

(sub-silt size) clasts occur (06LM105). These

clasts are rounded and can be particularly large

(up to 1.5 metres) and are concentrated near

the base of the layer, where they are aligned

along the layering. The almejas are mainly

composed of tubular pumice, which was

compacted moderately. Flow deformation

around phenocrysts can be observed in the

tubular pumice. A second type of pumice has

larger round vesicles with thicker walls. Next

to pumice, the sample contains plagioclase,

quartz, augite and Fe-Ti oxide crystal clasts

and porphyritic or mosaic type volcanic

fragments. The rock is grain supported, but

large thick bubble wall shards with remains of

large round vesicles occur. The sequence is

fining upwards and the top consists of grey

hard dense tuffs with a mottled structure

(09LM012). This sample is mainly composed

of glass shards, derived from tubular pumice

and contains some angular quartz crystal

clasts. The reddish clasts occurring at the base

of the sequence, are composed of a mixture of

angular fractured crystal clasts, pelagic

microorganisms, limestone fragments and

irregularly shaped to angular glass, some

strongly compacted in situ (06LM105).

The contact with the next sequence was not

observed. A coarse almeja sequence occurs at

09LM013. The main component is tubular

pumice but some andesitic volcanic clasts

occur (mosaic and microlitic type). Pumice is

compacted between harder volcanic clasts,

resulting in a low intergranular porosity.

Quartz, augite, alkali feldspars and Fe-Ti

oxides are present as crystal clasts or as

phenocrysts in the pumice. The upper part of

the sequence is similar as the lower part, at the

top centimetre size round to oval holes occur

(09LM014).

The sequence is eroded at the top by a new

almeja sequence (09LM015). In this unit a

metre size hole was observed. This sequence is

composed mainly of large tubular pumice,

which is compacted around quartz and feldspar

phenocrysts and microlitic volcanic particles.

There is no evidence of a fine matrix. The unit

is fining upwards into a fine-grained hard and

dense green, well cemented rock (09LM016).

Tubular pumice in this part is similar as in the

lower part, but a second type of pumice with

large round to irregular vesicles occurs. A third

type of pumice, which contains flow structures

around phenocrysts, is strongly compacted.

Crystal clasts are fractured, zoned feldspar and

augite. No fine matrix is observed. The

uppermost part of the sequence is a very fine,

relatively hard tuff.

The next sequence is incompetent at the base

and is fining upwards into a brown hard

competent tuff (09LM017). The rock is a

mixture of tubular pumice, less vesiculated

pumice with thicker walls, glass shards and

crystal clasts. Because of the high-grade of

alteration it is difficult to recognize the original

structures. The overlying sequence is

extremely hard and is composed of similar

material as the previous sequence. It is also

highly altered (09LM018). It grades upwards

into grey hard tuffs which further grade into a

green tuff at the top of the sequence

(06LM019). The upper part is composed of

fine tubular glass shards and pumice shards,

which occur together with tubular pumice and

larger pumice clasts with larger round to

irregular vesicles and thicker walls. Plagioclase

and pyroxene occur mainly in strongly

compacted flow banded pumice.

On top of this, a new thick almeja sequence

occurs, which is incompetent at the base

(09LM020). The base is composed of mainly

thick wall to large round vesicle type pumice

and some, more tubular pumice. A large

amount of large quartz and alkali feldspar

crystal clasts occur, or are present as

phenocrysts in the pumice. The pumice is

strongly compacted around these crystal clasts.

In some parts of the rock, a fine matrix is

observed. Higher, the sequence is fine-grained,

greenish and cross-cut by a large amount of

white veins.

The next thick sequence has an upper layered

part, which is coarser than the lower massive

part. The upper part is composed mainly of

tubular pumice and contains a large amount of

quartz and feldspar phenocrysts (09LM021).

The sequence is covered by a light-brown fine

tuff, composed of blocky angular glass shards

(09LM022).

Above this, a new fining upwards almeja unit

occurs (09LM023). The base is composed of

large pumice with large round to irregular

vesicles, tubular pumice and volcanic particles


79

(microlitic or perlitized). Large quartz and

feldspar phenocrysts occur in the pumice and

vesicles are folded around them.


Formation

A first sequence is composed of tubular

pumice, minor pumice with larger round

vesicles and thicker walls, different types of

volcanic clasts (mosaic type, microlitic,

porphyritic) and a high amount of fractured

quartz, pyroxene, feldspars and Fe-Ti oxides

(09LM024). Higher in the sequence, the

amount of tubular pumice increases and

crystals are only present as large phenocrysts

in the pumice. Microlitic and perlitized

volcanic particles occur (09LM025). Sample

09LM026 at the top of the sequence, is

composed mainly of finer tubular pumice and

glass shards. Some pumice is highly

compacted.

The sequence is covered by a new coarse and

thick unit, which contains centimetre size holes

near the base (09LM027). The basal part is

composed mainly of compacted tubular

pumice. The sequence is fining upwards. At

this point it is not clear if a new sequence starts

or if this part is the upper part of the previous

sequence. Sample 09LM028 consists of large

clasts of tubular pumice and some large quartz,

feldspar, pyroxene and Fe-Ti oxides, which

occur as crystal clasts or in the pumice, and

some volcanic clasts occur. Near the top, the

sequence is composed of layered almejas.

Sample 06LM108 consists of tubular pumice

and pumice with round vesicles which is

embedded in a matrix of glass shards and

fractured quartz, plagioclase and pyroxene

phenocrysts. The upper part of the sequence is

composed of a hard tuff (09LM030), which is

topped by a grey limestone layer (09LM031).

Sample 09LM030 is a glass shard tuff, which

is composed of blocky shards and elongated

shards derived from tubular pumice.

The limestone layer of the previous sequence

is covered by fine-grained brownish to greyish

lapilli tuffs with a white matrix (Samples

06LM109-110, 09LM032). Large holes are

observed in this sequence (GPS 09-39). This

sequence is highly altered and it is therefore

difficult to recognize its original components.

Crystal clasts of quartz, feldspar and Fe-Ti

oxides are recognized. Some areas are replaced

by clays and could have been strongly

compacted pumice.

Section 3 of the Lower unit of the Cayo

Formation

Higher in the section, no continuous outcrops

are exposed and therefore it is not possible to

determine how many sequences occur or how

thick they are (GPS 09–39 to 09–50 and

samples 06LM112–114, 09LM033). Lapilli

tuffs are iron brown, dark grey to kaki green,

can be strongly weathered and are intercalated

with thin greenish red to brown tuff beds.

Some accessory red clasts up to 60 cm in size

occur. Sample 09LM033 contains a high

amount of different types of andesitic volcanic

clasts, pumice with large irregular vesicles,

some tubular pumice and feldspar crystals.

Many components are difficult to identify

because of the high degree of alteration. Lapilli

tuffs contain generally mainly brownish to kaki

flattened pumice and different types of

volcanic clasts. The lapilli tuffs are well sorted,

and when no fine matrix is present a white

mineral fills pores between the clasts

(06LM113–114, 09LM35). Sample 06LM113

is composed of pumice clasts with large round

to irregular to stretched vesicles. It also

contains a lot of vesicular volcanic particles.

Other volcanic particles are porphyritic, with

an intergranular matrix or with feldspar laths

and contain pyroxene phenocrysts. Quartz

occurs as a phenocryst in some volcanic

particles. Other volcanic particles have a fine-

grained mosaic matrix. No fine matrix occurs

between the clasts. Samples 09LM035 and

06LM114 are similar in composition, but also

contain tubular pumice.

A gradual evolution towards a thick light

greenish almeja sequence can be observed

(GPS 09–049–051). This sequence has a

massive lower part (09LM036–038), which is

similar in clast composition as the lower

sequences, but contains a higher amount of

tubular pumice, which is moderately

compacted. Higher in the sequence (sample

09LM038, 06LM116) tubular pumice is the

most important component. Vesicles are larger

in size and are bended off around phenocrysts.

Compaction is larger higher in the sequence.


80

The sequence is fining upwards and layered in

the upper part (09LM039, 06LM116), although

it is possible that this layered part composes a

new sequence. Sample 09LM039 contains

more quartz, feldspar and augite phenocrysts

and is composed mainly of pumice with small

stretched thick wall pumice. Sample 06LM116

of the layered part, contains again pumice with

larger stretched vesicles. The sequence is

topped by a dark grey fine-grained siltstone

(09LM040). Because of the strong competence

of the almeja sequences, a second large

waterfall is present at this location.

This unit is covered by numerous metre thick

sequences of lapilli tuffs with compaction

structures which are interbedded with reddish

green fine-grained tuffs (09LM041–043).

Sample 09LM042 is a lapilli tuff similar in

composition as the previous sequence. Pumice

is typically tubular, but larger stretched

vesicles occur. Pumice is stretched around

quartz phenocrysts. In this sample a disk-type

foraminifera is observed.

5.2.4 The upper part of lower unit

Higher in the section, beds become more fine-

grained and are very hard and competent. At

this point, the Río Guaraguao bends off to the

northwest, and follows the strike of these

competent rocks for about a kilometre, where it

bends off again to the SW, perpendicular to the

strike. Sample 06LM118 is the contact of a

fine tuff with a lapilli tuff. The fine tuff is

composed mainly of blocky glass shards. It has

no internal lamination. The lapilli tuff is

composed mainly of pumice of tubular shape

or pumice with small stretched vesicles and

thick walls. Some porphyritic volcanic

particles with a black to dark grey

microcrystalline matrix occur. Sample

06LM123 is composed mainly of blocky to Y-

shaped glass shards. The sample is well sorted

but no internal lamination occurs.

A thick unit of brown incompetent lapilli tuffs

with onion weathering structures occurs. These

are intercalated by thin (<50 cm) brown to

yellow tuff layers (06LM176–179). Sample

06LM178 consists mainly of pumice with

small round vesicles and thick walls and a high

amount of plagioclase (polysynthetic twins),

augite and dark prorphyritic volcanic

fragments. Sample 06LM176 consists mainly

of strongly compacted tubular pumice and

contains some pyroxenes, plagioclase and dark

porphyritic volcanic fragments.

At GPS 06–124 a brown tuff is in contact with

a unit of dark brown lapilli tuffs (06LM124,

04LM008). These are covered by a green tuff

layer, a 50 centimetre thick black compacted

lapilli tuff sequence and again a greenish tuff

layer (06LM074–78). Sample 06LM074 is

composed almost entirely of tubular pumice

clasts. Some large phenocrysts of mainly

plagioclase and augite occur. Bubbles are

bended off around the phenocrysts. Rare dark

porphyritic volcanic fragments occur. The

greenish tuffs are light in weight,

homogeneous and have no internal lamination.

Only the upper 1.5 metres of the next sequence

were observed. A coarse-grained fining

upwards sequence of lapilli tuff with a purple

matrix colour occurs. Sample 06LM079 is

composed of large clasts of pumice, which can

be tubular, or pumice with large vesicles with

thick walls. Next to pumice, volcanic schlacke

with a matrix of fine feldspar laths and large

irregular to round vesicles and some dark

porphyritic volcanic fragments occur. Some

pumice is strongly compacted. Some accessory

red clasts which are up to 20 cm in size occur

in the lapilli tuffs. The lapilli tuffs are overlain

by green tuff layers, which are covered by

coarse-grained lapilli tuffs. This second lapilli

tuff sequence is topped by porous green tuffs

and light beige tuffs (06LM082), which are

intensely veined with calcite. Sample

06LM082 is pervasively altered and it is

difficult to identify its original components.

On top of this, a fining upwards intensely

veined sequence of beige-green banded

competent lapilli tuffs occurs (06LM085). The

sample is highly altered, but remaining tubular

pumice is visible. Quartz, amphibole and Fe-Ti

oxides occur as crystal clasts and in the

pumice. Sample 06LM087 is a beige,

competent, well cemented breccia consisting of

very angular fragments. Because of the high-

grade of alteration, it is difficult to see what the

original components were, but the presence of

microorganisms and the high amount of

calcite, suggest that the sample contains an

amount of sedimentary material. It is covered

by fine green compacted lapilli tuffs.


81

The next sequence consists of a green tuff with

flaser bedding, covered by 80 centimetres of

almejas, which are covered by thin sequences

of green tuffs and brown lapilli tuffs and a

metre thick fine lapilli tuff (09LM046–049).

The sequence is repeated above, possibly

because of a fault contact (GPS 09–69–071).


Formation

At this point a fault (inferred) changes the

strike of the layers. A tuff underlies a sequence

of compacted green lapilli tuffs (09LM051–

056). Sample 09LM052 at the base of the

sequence contains a high amount of

polysynthetic or zoned plagioclase crystal

clasts and minor pyroxene and Fe-Ti oxides.

Next to crystal clasts volcanic schlacke and

andesitic volcanic particles occur (mosaic,

microlitic). Both pumice with round vesicles

and thick walls and tubular pumice occur.

Tubular pumice is compacted between the

harder volcanic and crystal clasts. Sample

09LM053 is similar in composition, but

pumice is more abundant, is larger and has

larger vesicles. The vesicle type varies from

fine tubular to large stretched to smaller thick

wall vesicles and vesicles are bended around

phenocrysts. Sample 09LM054 is similar in

composition, but clasts are smaller in size.

Some larger pumice is strongly compacted.

Sample 09LM055 has somewhat smaller clasts

but contains some large pumice clasts. The

number of crystal clasts is higher than in the

previous sample, so possibly this could be the

base of a new sequence. Sample 09LM056 is

composed of smaller tubular pumice and fine

Y-shaped glass shards.

The sequence is covered with thin lapilli tuff

and tuff beds (09LM057–059). Sample

06LM088 contains microorganisms. Higher, a

second thinner compacted lapilli tuff sequence

occurs (09LM060–062). Sample 06LM090 is

composed mainly of compacted tubular

pumice, but contains also some large shards

which originate from pumice with very large

round vesicles. This sequence is covered by a

grey tuff, a fine lapilli tuff and a thick layer of

white tuffs (09LM063–066). These white tuffs

are composed of tubular pumice with very

small vesicles but contain also very large Y-

shaped glass shards which can not originate

from the same pumice (sample 09LM066).

These are covered by grey tuffs (09LM068–

069).

In the last few metres of the lower unit of the

Cayo Formation, large lithological variations

are present. The following lithologies are

observed near the top: brown tuffs, green

compacted lapilli tuffs, a fine strongly

compacted beige lapilli tuff, a beige tuff, a

dark grey tuff, a homogenous beige tuff, a

black heavy laminated tuff, a black competent

heavy tuff, a beige tuff heavily eroded by a

beige sandstone (06LM127). The top of the

lower Cayo Formation is placed at this point.

Above this point, no typical greenish or beige

homogenous lightweight tuffs, almeja

sequences or green lapilli tuffs rich in tubular

pumice occur. Sample 06LM129 is a mixture

of crystal clasts (plagioclase and augite),

tubular pumice, pumice with large round to

irregular vesicles and different types of

andesitic volcanic clasts (mosaic, microlitic).

This sample contains some limestone particles

and has a fine micritic matrix.

5.3 The upper unit of the Cayo

Formation

5.3.1 The base of the upper unit of

the Cayo Formation

The base of the upper unit of the Cayo

Formation is composed of numerous thin beds

of different lithological types (06LM128-144).

Characteristic is a several metre thick unit of

dark grey hard and dense fine-grained rocks.

When cut, the rocks are dark brown, blue,

green, grey to black in colour, of sub-silt to

sand grain size and several rocks are

characterized by an internal lamination. They

can contain erosional surfaces, with alternation

of silt and sand size layers, can be bioturbated

and contain soft sediment deformation

structures. These rocks are much heavier than

the tuffs of the upper part of the lower unit of

the Cayo Formation and can easily be

distinguished. The fine-grained rocks are

intercalated with thin beds of fine well-sorted

lapilli tuffs which have clasts of silt to pebble

size and larger accessory green clasts. They are

very heterogeneous in clast composition and


82

all are cemented by a white mineral. As the

fine-grained rocks, they can be laminated, can

have erosional surfaces and can be fluidized or

bioturbated.

These fine-grained lithologies contain crystal

fragments, blocky glass and pumice fragments,

and a high amount of foraminifera and

radiolaria. Interlayered lapilli tuffs contain

basaltic and orange reddish andesitic

fragments, blocky glass fragments and

different kinds of pumice (06LM136-145,146).

Sample 06LM135 is a laminated siltstone

composed of blocky glass fragments derived

from pumice with thick walls and round

vesicles, limestone fragments, a high amount

of pelagic microorganisms and rounded to

angular crystal fragments of quartz, feldspar,

augite and Fe-Ti oxides. Sample 06LM136 is a

fine lapilli tuff composed of irregular

compacted pumice, a high amount of angular

crystal clasts of plagioclase, K-feldspar, augite,

andesitic volcanic fragments, some reddish

vesicular volcanic fragments and limestone

fragments embedded in a fine ash matrix.

Sample 06LM138 is a laminated tuff

composed mainly of small blocky glass and

pumice clasts and some crystal clasts. Pumice

has small round vesicles and thick walls. Clasts

are quite angular and embedded in a

microcrystalline matrix. Some pelagic

microorganisms are present. The clasts are

quite well sorted.

5.3.2 The lower part of the upper

unit of the Cayo Formation

At this point, the river splits up and the eastern

branch is followed. Fourty meters are not

visible in outcrop. In this part of the section

lapilli tuff sequences are thicker and clast size

is larger compared to the underlying part. The

thick lapilli tuff sequences alternate with thin

beds of grey to black heavy tuffs (06LM145-

159). Lapilli tuffs are well sorted and fining

upwards and contain clasts of three to four

centimetres at the base of the sequences to a

few millimetres at the top. Accessory red fine-

grained clasts can be up to 20 centimetres in

size. The contact of the lower coarse part of a

sequence with the upper grey heavy tuff part is

sharp. Individual sequences can be up to 30

meters thick, though it could not be excluded if

these beds consist of one or multiple

depositional units. Some lapilli tuffs are well

cemented and hard, while others are strongly

weathered and iron-brown in colour. Individual

differently coloured clasts are easily visible

and are cemented together by a white cement.

In some samples this cement fills only part of

the pores resulting in a very bad cohesion of

the rocks.

These lapilli tuffs are predominantly composed

of non-vesiculated to vesiculated to compacted

pumice. Volcanic clasts can make up to 40%

of the rocks and are basaltic porphyritic to

reddish or grey andesitic with feldspar laths

and pyroxene. In some rare fine-grained layers

blocky glass shards occur.

Sample 06LM145 is a fine lapilli tuff

composed mainly of well sorted and rounded

effusive volcanic clasts and crystal clasts. The

clast types are: effusive dark porphyritic,

greyish microlitic and orange-brown volcanics,

all are rich in phenocrysts. Rounded crystal

clasts are mainly plagioclase and some K-

feldspar, amphibole and Fe-Ti oxides.

Schlacke with irregular vesicles occur. Pumice

is rare, different types occur: pumice with thick

walls, irregular vesicles, stretched vesicles,

tubular vesicles. Some microorganisms are

present. Sample 06LM146 is composed of

different types of well crystalline and well

rounded effusive rock fragments and schlacke

embedded in a fine matrix which contains

some blocky glass and pumice fragments, algal

and pelagic microorganisms. Sample

06LM148 is a tuff composed mainly of small

sized angular glass, pumice and feldspar

crystal clasts, some rounded dark porphyritic

volcanic fragments, tubular pumice and some

pumice with larger stretched vesicles,

containing augite phenocrysts and some

pelagic microorganisms. No internal

lamination is present. Sample 06LM149 is a

coarse lapilli tuff composed mainly of angular,

well crystalline andesitic effusive volcanic

fragments, schlacke, some reddish volcanic

fragments, some fragments containing

recrystallized spherulites and minor pumice.

Pumice has thick walls and large round

vesicles and can be compacted. No fine matrix

is present. Sample 06LM150 is a fine lapilli

tuff composed of volcanic clasts, pumice and

crystal clasts. Volcanic clasts are black to

orange brown porphyritic or microlitic. Pumice

is larger than other particles and has large


83

irregular to stretched vesicles and is compacted

between the harder clasts. Some smaller

pumice clasts with only 2 to 3 round vesicles

are present. Volcanic clasts are moderately

rounded, but pumice is not rounded. Crystal

clasts are large rounded plagioclase, pyroxene

and Fe-Ti oxides. Some foraminifera occur. No

fine matrix occurs. Sample 06LM153 is a

lapilli tuff composed mainly of rounded

porphyritic effusive clasts, others volcanic

clasts with interterstal texture, large pumice

clasts with round vesicles and thick walls

containing feldspar phenocrysts. No fine

matrix occurs. The sample contains a red

boulder which is composed mainly of blocky

glass shards and some pelagic microorganisms.

Sample 06LM154 is a coarse lapilli tuff

composed of different types of porphyritic to

well crystalline effusive volcanic clasts (some

reddish in colour), schlacke and large pumice

clasts with round to elongated or irregular

vesicles. No fine matrix is present. Sample

06LM155 is a coarse lapilli tuff composed of a

large variety of rounded volcanic clasts,

schlacke, pumice with large regular vesicles

and thick walls, pumice with small rounded

vesicles, pumice with thin walls, pumice with

irregular vesicles. This sample is uncompacted

and no fine matrix occurs.

The next part of the section is not well exposed

in outcrop, but the main lithologies observed

are thin layers of fine-grained lapilli tuffs and

tuffs. It differs from the underlying unit

because of the appearance of greenish

laminated tuffs (e.g. sample 06LM160). This

lithology is characteristic for the upper Cayo

Formation. The difference with the

homogeneous porous tuffs in the lower unit of

the Cayo Formation is that these tuffs are

laminated, heavier and less porous. Laminae

show centimetre to millimetre fining upwards

sequences of sand to clay size, are ondulating

and erosive and show fluidisation structures.

Sand- and silt size laminae are greenish to

bluish, while clay-rich laminae are brownish.

The following lithologies are observed: black

heavy siltstone (6m), intercalated with two thin

beds of beige lutites (30cm, 06LM160);

siltstones; fine lapilli tuffs (sand size); green

tuffs with fluidisation structures (06LM161);

fine lapilli tuffs (sand size); a coarser yellow

lapilli tuff (06LM162); a green tuff with

fluidisation; grey heavy siltstones; fine-grained

lapilli tuffs interstratified with dark brown

siltstones (or fine lapilli tuffs) (06LM163),

topped by a green tuff bed (06LM164); fine

homogeneous lapilli tuffs (sand size)

(06LM164). This part of the section consists

mainly of fine-grained lithologies composed

mainly of blocky glass shards (up to 100%)

and some vesiculated pumice, crystal clasts

and volcanic fragments. Coarser lithologies

consist mainly of pumice.

Sample 06LM158 is composed mainly of

blocky glass shards and angular crystal clasts

and some rare pelagic microorganisms. The

sample is laminated. Sample 06LM160 is a

laminated tuff composed mainly of fine glass

shards and some crystal fragments and mica

flakes. Algal fragments and pelagic

microorganisms occur. Erosive surfaces occur

between the laminae. Sample 06LM161 is a

fine laminated tuff composed entirely of

acicular glass shards. Sample 06LM162 is a

fine-grained lapilli tuff composed mainly of

pumice and some schlacke, dark porphyritic

and reddish effusive volcanic clasts,

plagioclase, Fe-Ti oxide and pyroxene crystal

clasts and some rare pelagic microorganisms.

The most common pumice clasts have round

vesicles and thick walls, others have more

irregular vesicles and some of the pumice is

compacted. Clasts are quite angular and quite

well sorted. Sample 06LM163 is a laminated,

well sorted tuff composed mainly of blocky

glass shards, some crystal clasts and pelagic

organisms. Sample 06LM165 is a laminated

and well sorted tuff composed of blocky glass

shards and angular crystal clasts of plagioclase,

minor pyroxene and Fe-Ti oxides and some

small black porphyritic clasts.

5.3.3 The middle part of the upper unit of the Cayo Formation

In the next part of the section, lapilli tuff

sequences are thicker, coarse-grained and most

lapilli tuffs are well cemented and competent.

In most rocks, different types of angular to

well-rounded clasts are present embedded in a

bluish green matrix. This type of lapilli tuff is

characteristic for the middle part of the upper

unit of the Cayo Formation. Next to the

greenish laminated tuffs with fluidisation

structures, a dark grey very fine-grained (clay

size) competent homogeneous tuff is present,


84

which is also characteristic for this part. At the

top of the middle part, a thick sequence of light

brown tuffs can be observed. 06LM166 is a

sample of a first coarse lapilli tuff sequence.

The sequence is fining upwards. The rocks are

grey in outcrop and kaki-green on fresh cuts.

Matrix and clasts have the same colour, except

for some red clasts (up to 3 cm large). The

second lapilli tuff sequence (06LM168) erodes

the fine lapilli tuffs of the upper part of the

previous sequence and has a light brown

matrix, and a large variety in clast types. The

top of these lapilli tuffs is in sharp contact with

a 2 meter thick laminated brown-green tuff

sequence.

Sample 06LM167 is a well sorted tuff

composed mainly of blocky glass shards,

pumice and black volcanic fragments. Pumice

contains small vesicles and has thick walls and

some tubular pumice occurs. Crystal clasts are

feldspar, augite and Fe-Ti oxides. Some

prismatic clasts composed of calcite are

probably of organic origin and pelagic

microorganisms occur. Sample 06LM168 is a

lapilli tuff composed of effusive volcanic clasts

and minor pumice clasts, some algal and

limestone fragments and feldspar crystal clasts

occurring in a fine matrix. Rock fragments are

dark porphyritic volcanics, schlacke and red

vesiculated volcanic fragments. Pumice has

round to elliptical vesicles, thick walls and is

small in size. Sample 06LM170 is a laminated,

well sorted tuff composed of blocky rounded

glass shards, some black effusive volcanic

fragments, Fe-Ti oxides which are

concentrated in bands and pelagic

microorganisms. Sample 06LM169 is a well

sorted and well laminated tuff composed

mainly of acicular to Y-shaped glass shards,

some angular feldspar and quartz crystal clasts

and pelagic microorganisms. Sample

06LM171 is a well sorted lapilli tuff composed

of effusive volcanic clasts and pumice in a

vitroclastic matrix. Volcanic clasts are

porphyritic or microlitic with larger

plagioclase phenocrysts and can be

vesiculated. All volcanic clasts are quite well

rounded. Pumice is tubular or has thick walls

and large vesicles and is irregular in shape.

Crystal clasts are pyroxene and amphibole.

Glass is irregular to blocky. Some limestone

fragments, algal fragments and pelagic

microorganisms occur.

Below the third lapilli tuff sequence, a thin

layer of green laminated tuffs occurs. This

sequence is also fining upwards. On top of this

sequence a series of thin beds occurs: a

laminated dark green-brown sandstone with

flattened green clasts (06LM172); a lapilli tuff

(4-5m); green tuffs; a brown green laminated

tuff (06LM174); a light green tuff; a fine grey

lapilli tuff (1m); a light green tuff; a fine grey

lapilli tuff; a brown tuff (2-3m); a fine grey

lapilli tuff (1m); a brown tuff (2m); a grey

lapilli tuff (1m); a white tuff (3m), green

laminated when cut; a fine grey lapilli tuff

(1,5m); a brown tuff (2m); a fine grey lapilli

tuff (2.5m); a brown tuff.

A fourth and a fifth competent lapilli tuff

sequence occur with clasts up to 5 cm large.

The matrix is light green to white

(macroscopic crystals) and different types of

clasts occur (06LM182-183). Between the two

sequences a porous green lightweight tuff

occurs. On top of the fifth sequence a very fine

homogeneous competent grey lutite is

deposited (06LM184), which evolves into a

grey laminated lutite. Sample 06LM182 is a

coarse lapilli tuff composed of andesitic well

crystalline volcanic particles, schlacke,

pumice, glass shards, crystal clasts, algal

fragments and pelagic microorganisms.

Pumice can be tubular or has thick walls and

round vesicles. Glass shards are irregularly

shaped, blocky or Y-shaped. Crystal clasts are

plagioclase, pyroxene and Fe-Ti oxides. No

fine matrix is present. Sample 06LM180 is a

lapilli tuff composed mainly of coarse volcanic

fragments and some pumice, and large

plagioclase and pyroxene crystal clasts.

Pumice has small round to large irregular

vesicles with thick walls. Volcanic fragments

are schlacke, red porphyritic effusive, black

vesiculated, or porphyritic with a fine

crystalline matrix. The clasts are embedded in

a fine matrix composed of large blocky shards

with large vesicle walls and smaller tubular or

acicular shards, algal fragments and pelagic

organisms. An erosive contact is seen with a

fine-grained bed composed of glass shards and

pelagic organisms embedded in a fine-grained

matrix.

The next thin lapilli tuff sequence is topped by

light brown tuffs (06LM187). A sixth coarse

competent lapilli tuff sequence with a green

matrix and different kinds of clasts occurs


85

(06LM188). The base is very erosive, clasts

are very coarse, and both angular and rounded

at the base (7-8 cm). Further from the base,

clasts are more homogeneous in type and size.

The sequence is fining upwards into a brown

homogenous lapilli tuff (06LM189). It is

deposited as wedge-shaped meter size banks.

The uppermost part of this sequence consists

of a thick layer of light brown fine

homogeneous tuffs (06LM190) that evolve

into laminated brown tuffs at the top

(06LM196). In the middle of this tuff layer a

thin fine-grained lapilli tuff layer is present

(06LM194). On top of these brown tuffs two

thin sequences of thin green lapilli tuffs and

thin green tuffs are present.

Fine lithologies are similar as in the lower part

and consist mainly of blocky to elongated glass

shards, aligned along the layering (06LM169-

171, 187,190,191,196). Crystal clasts and

pumice also occur. Sample 06LM190 contains

a large amount of pelagic organisms next to

glass shards. Coarse lithologies consist of

pumice (vesiculated to non-vesiculated, some

compacted) and basaltic (porphyritic,

interterstal) to andesitic (reddish) clasts, crystal

clast and in some cases (06LM180,188) blocky

glass shards.

Sample 06LM187 is a laminated, well sorted

tuff. It is composed of blocky glas shards,

contains quite much pelagic organisms and

some crystal clasts. Sample 06LM188 is a

coarse lapilli tuff composed of different types

of volcanic clasts. Most clasts are well

crystalline, with a microcrystalline matrix and

larger phenocrysts or schlacke. The clasts are

embedded in a fine matrix which contains

angular plagioclase and Fe-Ti oxide crystal

clasts, small pumice clasts of both tubular and

thick wall types, large blocky shards with

remaining bubble walls, finer grained Y-

shaped glass shards and fine blocky shards.

Algal fragments and pelagic microorganisms

are quite common.

Sample 06LM190 is a laminated, well sorted

tuff composed of acicular fine glass shards and

pelagic microorganisms (20%). Some small

volcanic rock fragments and crystal clasts

occur. The clasts are embedded in a fine

matrix. Sample 06LM191 is a laminated, well

sorted tuff composed of irregularly shaped

blocky to prismatic shards and some crystal

fragments embedded in a fine matrix. Sample

06LM194 is a fine lapilli tuff composed

mainly of pumice and minor angular

plagioclase, quartz, pyroxene and Fe-Ti oxide

crystal clasts. Rock fragments are less

common. Different types occur: black

porphyritic and interterstal effusive volcanic

clasts, some vesiculated and reddish volcanic

clasts, schlacke, grey microcrystalline andesitic

clasts. Organic fragments are quite abundant.

Tabular organic fragments and algal fragments

occur. The sample is well sorted and fragments

are moderately rounded. Sample 06LM196 is a

laminated, well sorted tuff composed mainly of

aligned acicular glass shard and Y-shaped

glass shards. Some blocky shards occur.

Sample 06LM198 is a lapilli tuff composed

mainly of effusive volcanic fragments. The

main type of clasts are schlacke, brownish in

colour, with irregular vesicles. Coarse-

crystalline volcanics are less common, some

interterstal volcanic fragments occur, and some

fragments with spherulitic texture and red

effusive fragments. Pumice is less common

(20%) and has large round to irregular vesicles.

Some algal and pelagic organisms occur, no

fine matrix is present.

5.3.4 The upper part of the upper unit of the Cayo Formation

The upper part of the Cayo Formation

demonstrates a clear cyclic pattern. It consists

of thin sequences of lapilli tuffs containing

brownish to greenish particles that are mostly

not well cemented. These lapilli tuffs are

frequently strongly weathered and have an iron

brown colour. All sequences are fining

upwards. The lapilli tuffs are in sharp contact

with brown to green laminated fluidized tuffs.

In most sequences the lapilli tuff part is thicker

than the tuff part, though the opposite is

possible.

29 lapilli tuff – tuff sequences were

distinguished in this part. Sequence 1 is a thin

sequence of 3 meters (lapilli tuff + tuff). The

lapilli tuff part consists mostly of light brown

particles, well compacted, without the green

cementation typical for the middle part of the

upper Cayo Formation. It is poorly sorted and

incompetent (06LM201). Most of the

sequences in this part are similar in

appearance, only the total thickness and the


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thickness of the lapilli tuff and tuff part in each

sequence differs. The sequences that differ

somewhat from this general model are

described here: The lapilli tuff of sequence 4 is

very competent, greenish and with pervasive

alteration (06LM067). Below this lapilli tuff, a

very competent heavy black sandstone occurs

(06LM068). The base of sequence 16 consists

of green competent lapilli tuffs with green

flattened particles (06LM061).

Because of the presence of a thrust fault

between sequences six and seven, it is possible

that part of the Cayo Formation is missing

here. Light beige powder material is found in

this fault zone (06LM065).

Sample 06LM068 is a well-sorted fine lapilli

tuff, composed of porphyritic and vesicular

black clasts and irregular to blocky pumice

shards. Crystal clasts (10%) are plagioclase,

Fe-Ti oxides, pyroxene and quartz. Some

pelagic organisms and limestone fragments are

present. Sample 06LM067 is composed mainly

of pumice. It has irregular to round vesicles but

some is not vesiculated and some has

phenocrysts. Some pumice is compacted. Rock

fragments are smaller than the pumice

particles, are black to brown porphyritic or

schlacke. Some rare volcanic fragments with

mosaic texture occur. Crystal clasts are quite

common and are amphibole and pyroxene.

Some algal and pelagic organisms occur.

Sample 06LM070 is a lapilli tuff composed of

different types of volcanic clasts. Clast types

are: andesitic or with felsitic texture, others are

coarsely crystalline, some are reddish, others

black vesiculated or schlacke. Glass and

pumice are rare. No fine matrix is present.

Sample 06LM064 is a laminated vitroclastic

tuff composed of acicular fine glass shards.

Sample 06LM061 is a compacted lapilli tuff

composed mainly of pumice. Pumice has

irregular small to large vesicles and some

tubular pumice occurs. Some volcanic

fragments occur which are black to red

porphyritic. Some pyroxene crystal clasts,

pelagic organism and calcite prisms (algal?)

occur. Sample 06LM060 is composed of

irregular glassy particles, blocky angular

shards, pumice with thick walls or stretched to

irregular vesicles. Volcanic clasts are larger

than glassy particles, brown, black or grey with

interterstal or microcrystalline texture. Crystal

clasts are angular plagioclase and minor

pyroxene, Fe-Ti-oxides, augite and K-feldspar.

Some rare pelagic organisms occur.

Section 1 of the upper unit of the Cayo

Formation

In the uppermost part some sequences have

been sampled in detail (sequence 20: 06LM42-

59 and sequences 28-29: 06LM30-39).

Coarse rocks at the basal part consist

predominantly of pumice or of pumice and

coarse black to brown volcanic particles. In

sample 06LM061, the pumice is clearly

welded. In finer grained rocks the same

components occur associated with irregularly

shaped glass, crystal clasts, some algal

fragments and pelagic organisms.

Samples 06LM058,057,047,053,051,049,044

belong to the same sequence. Coarse lapilli

tuffs are composed mainly of vesiculated

pumice and some basaltic rocks fragments.

Finer tuffs are composed of glass shards. The

finest rocks consist of pelagic organisms

(radiolaria and foraminifera) embedded in a

fine-grained matrix. It is not clear if this matrix

was originally build up of glass or not, no

primary structures are preserved. The

uppermost lapilli tuff – tuff sequence of the

Cayo Formation, near the contact with the

Guayaquil Formation, consists of similar lapilli

tuffs, fine-grained glass-tuffs with blocky glass

shards interlayered with pelagic layers rich in

microorganisms (06LM032-035).

Sample 06LM058 is a fine-grained well sorted

laminated tuff composed of irregular glass

shards, plagioclase and Fe-Ti oxide crystal

clasts and some rare pelagic organisms.

Sample 06LM057 is a coarse lapilli tuff

composed mainly of pumice with large

irregular vesicles and thick walls rich in

phenocrysts. Rock fragments (30%) are black

porphyritic and vesiculated effusive clasts,

coarse crystalline volcanic rocks, orange red

volcanic rocks and brown schlacke. Crystal

clasts are amphibole and augite. All clasts are

angular. Sample 06LM054 is a massive well

sorted tuff composed of acicular glass shards.

Sample 06LM053 is a laminated tuff

composed of blocky glass shards, pumice

shards with round bubble walls and angular

shards. Some feldspar crystal clasts occur.


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Sample 06LM051 is a very fine laminated

fallout with a fine matrix. Pelagic organisms

are common (20-30%). Sample 06LM049 is a

laminated tuff composed of Y-shaped to

blocky glass, angular glass shards, acicular

glass shards and pumice shards with round

vesicles and thick walls. Some rounded dark

brown glassy fragments occur. Quartz and

feldspar crystal clasts are rare and some pelagic

organisms occur.

Section 2 of the upper unit of the Cayo

Formation

Sample 06LM044 is a laminated siltstone with

a fine matrix and a high amount of pelagic

organisms. Sample 06LM043 is a lapilli tuff

composed mainly of pumice with perfectly

round to irregular vesicles and rare tubular

pumice. Volcanic fragments are dark

porphyritic effusive fragments, vesiculated

fragments, fragments with a microcrystalline

matrix and schlacke with large phenocrysts,

which are quite common. Some pyroxene and

Fe-Ti oxides crystal clasts occur. No fine

matrix is present. Sample 06LM036 is a

laminated tuff composed of blocky to acicular

glass shards and Y-shaped glass shards.

Crystal clasts are mica and some plagioclase.

Some rare pelagic microorganisms occur.


mainly of pumice with irregular vesicles. Some

fine tubular pumice occurs. Schlacke are

common and contain phenocrysts. Black

porphyritic and vesiculated effusive volcanic

clasts and perlitic clasts occur. Others have

intergranular or microlitic texture. Crystal

clasts are K-feldspar, plagioclase, pyroxene,

quartz and amphibole and are all angular and

fractured. All components are angular and

badly sorted. Sample 06LM034 is a lapilli tuff

composed mainly of pumice which is

irregularly shaped, has small vesicles, and is

compacted along the layering. Some tubular

pumice and some schlacke occur. Dark

porphyritic volcanic clasts and volcanic clasts

with mosaic texture and perlites occur. Crystal

clasts are angular plagioclase, pyroxene and

Fe-Ti oxides. The sample does not contain

much fine components. Sample 06LM033 is

composed mainly of pelagic organisms in the

bottom part, while the upper part is composed

of blocky glass shards and the uppermost part

of shards with thick bubble walls and fine

acicular shards. Sample 06LM032 is composed

of blocky glass shards and Y-shaped glass

shards (less common) in the lower part, while

the upper part is composed of pelagic

microorganisms embedded in a fine matrix.


mainly of pumice which is tubular or has large

round vesicles. Volcanic fragments are black

cryptocrystalline, microlitic, reddish or

schlacke. Some plagioclase and pyroxene

crystal clasts occur. Clasts are angular but

quite well sorted, and not much fine matrix is

present.


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Appendix 9 – Petrographical analyses of the alteration of the samples of the Río Guaraguao section

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9.1 Alteration in the Piñón

Formation

Only two samples were studied of the Piñón Formation (04LM095, 09LM072). One sample is effusive, the other subvolcanic. The samples are altered to fine-grained calcite which is spread in the groundmass of the rocks and to well crystalline coarse spherical relatively pure chlorite and greenish opal-CT occurring in amygdules. Feldspars are generally not, or only partially albitized. Alteration zones of opal and veins of quartz penetrate through permeable areas in the rocks. All opal-CT is recrystallised to quartz. No zeolites were found in the samples of the Piñón Formation.

9.2 Alteration in the Calentura

Formation

The fine-grained beds of the Calentura Formation have typically a high quartz (40-95%) and calcite contents (5-45%). Their matrix is fine-grained making it difficult to distinguish between different alteration minerals. Clay minerals are generally brownish and have high interference colours.

9.3 Alteration in the lower unit of

the Cayo Formation

9.3.1 Coarse breccia at the base of the Cayo Formation

Sample 09LM078 is pervasively altered, very few original structures can be recognized. The fine matrix contains calcite and a mosaic of quartz and albite. Laumontite occurs as larger crystals enclosing clasts and smaller crystals, among which are calcite and quartz. No fresh

feldspar crystal clasts occur, all are albitized or replaced by laumontite. Clay minerals occur and are brownish, coarse, spherical in form and have high interference colours. Iron oxides occur in cracks and at particle rims. Sample 06LM004 is altered to albite, quartz, laumontite and pumpellyite. Pumpellyite occurs as spherical yellow brown booklets in clasts and voids and in the matrix as microcrystalline aggregates intergrown in a mosaic of feldspars and quartz. Laumontite occurs in zones and is probably replacing clasts. Other clasts have a similar alteration type as the matrix. Sample 06LM003 is a large clast of the same breccia. It has a similar alteration as sample 06LM004 with mainly a fine-crystalline matrix of albite, quartz and minor pumpellyite, while clasts and crystal clasts (hornblende?) are replaced by laumontite and pumpellyite. Veins are composed of pumpellyite at their boundaries, while laumontite occurs more central.

‘Mottled’ lapilli tuffs

In sample 06LM085 similar observations can be made. Brown clays replace particles and occur in the matrix between clasts. An evolution can be seen from early formed red iron oxides to brownish, quite coarse clays to greenish clays. In some zones clays seem to be partially replaced by laumontite crystals enclosing albite, quartz, small iron oxide aggregates and anatase. Sample 06LM096 is a clast occurring in the grey mottled lapilli tuffs. It contains a high amount of yellow to light brown fine crystalline pumpellyite, which is intergrown with albite.

9.3.2 Lower part of the lower unit

Sample 06LM101 is a thin fine lapilli tuff occurring between two clayey beds and is composed mainly of pumice occurring in a fine

APPENDIX 9 - PETROGRAPHICAL ANALYSES OF THE ALTERATION OF THE SAMPLES OF THE RÍO GUARAGUAO SECTION


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altered glass matrix. Mordenite (60%) forms very fine radial aggregates in the matrix. Pumice is altered to iron brown smectite which rims vesicles while heu-type zeolites replace glass. Euhedral anatase crystals are quite common in this pumice. In other pumice, large heu-type zeolite crystals enclose large parts of the pumice. Glass shards contain no clay minerals, non vesiculated glass is mainly replaced by heu-type zeolites. Clays are relatively rare in the sample, they rim vesicles of some pumice, are the major component of some pumice clasts and occur as late phases in cracks. Feldspars contain round bubbles, which are filled with clays, mordenite replaces the rest of the crystal clasts. Calcite occurs as a late phase, forming large euhedral twinned crystals filling voids and also occurs dispersed through the matrix. Sample 09LM086 has a similar appearance as the mottled lapilli tuffs occurring below. Some zones of the sample contain more iron oxides, which rim particles and also contain completely argillitized particles which can have been pumice originally. Clays are brownish and have high interference colours. Other zones are lighter in colour, contain more laumontite, which occurs as larger crystals enclosing several smaller crystals of albite and quartz. Primary clays seem to be replaced by laumontite. Pumpellyite is quite common, but only occurs in a certain type of irregular particles, where it forms microcrystalline crystals or radiating bundles. Sample 06LM102 is a competent fine lapilli tuff. Because of the high degree of alteration, no primary structures can be recognized. The sample is build up of fine-grained randomly oriented interlocking laumontite, albite and quartz. Some larger particles, which were possibly pumice, are replaced by larger laumontite crystals. Clays form as late phases, are light to dark brown and seem to fill the remaining pore spaces. Sample 09LM088 is composed mainly of pumice. Fine-grained quartz preserves the pumice and vesicle outlines. Large albite and laumontite crystals, possessing undulous extinction, enclose these clasts. The distribution of albite and laumontite seems to be more or less random, as a pumice clast can be replaced at one side by laumontite and at

the other side by albite. All feldspar crystal clasts are albitized. Small clusters of anatase occur in the pumice. Clays seem to be rare to absent, some pumpellyite possibly occurs. Sample 09LM001 is pervasively altered, no primary structures are preserved, only feldspar crystal clasts can be recognized. These are albitized and are enclosed in large laumontite crystals. Sample 09LM089 is a typical fine-grained bluish green tuff occurring in the upper part of C1a. It is altered to heu-type zeolites and contains a high amount of quartz. Similar tuffs are exposed west of the section, where they are exploited. Sample 04LM009, obtained from a small zeolite quarry west of the section, is a glass shard tuff altered to quartz, mordenite and heu-type zeolites.

9.3.3 Middle part of the lower unit

Section 1 of the lower unit

Sample 09LM002 is from a tuff underlying the first almeja sequence. The sample is altered to albite, quartz and brownish clay minerals. A brownish incompetent clay bed underlies the first almeja sequence. Sample 09LM003 was taken from the lowermost observed almeja layer in the Río Guaraguao section. Some zones of the sample are replaced by fine crystalline alteration minerals (< 10 µm) and are almost isotropic. In other zones, where alteration minerals are coarser (100 µm to 2 mm), remains of spherical mordenite aggregates can be observed, but these are replaced by heu-type zeolites. Stilbite crystals, ranging from small and anhedral to very large in size (100 µm – 2 mm) also replace mordenite aggregates (50 µm). Individual stilbite crystals can replace several mordenite aggregates. Small impurities, probably of quartz and Fe-oxides, occur mainly in the outer rims and around spherical mordenite aggregates and preserve the shape of mordenite aggregates in these stilbite and heu-type zeolite crystals. Although a high amount of replaced mordenite aggregates can be observed in the sample, only 3 % of remaining mordenite is detected by XRD. Clays are relatively rare in the sample


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and are greenish in colour. XRD confirms the presence of a 10 Å clay, probably celadonite. Bedding parallel stylolites are formed late and are penetrating through all mineral phases. Stellerite was identified in the XRD pattern, but not in thin section. Plagioclase crystal clasts are albitized, as is confirmed by XRD. The sample is cross-cut by veins of laumontite and stilbite (09LM004) and is overlain by thin tuff beds. Sample 09LM005, from a second coarse-grained sequence, consists of a fine matrix which is composed of a fine mosaic of interlocking feldspar and quartz. Pumice clasts are replaced by large laumontite (up to 2 mm) and in some cases albite crystals. In these crystals vesicle outlines are preserved by fine-crystalline quartz (< 5 µm) or fluid inclusions which rim these vesicles. Remains of spherical mordenite aggregates can also be recognized, but these aggregates are larger and more loosely packed compared to sample 09LM003. In other zones laumontite forms smaller “puzzle type” crystals (40-200 µm). A large amount of feldspar crystal clast occurs, all are albitized. Fire red anatase occurs in pumice clasts. Clays are dark brown to orange in colour and occur around crystals clasts but also at the contacts of different laumontite crystals or in cleavages of laumontite crystals. These clays are thus formed after laumontite crystallisation or are redistributed during recrystallisation of primary clays. Some greenish clay minerals are present. Stylolites penetrate through all alteration minerals, including laumontite. Possibly some pumpellyite occurs as a late phase, but because of the low amount present, this could not be confirmed by XRD. This rock unit is overlain by incompetent brownish clays. Sample 09LM009 is a pervasively altered lapilli tuff. Its matrix is very fine-grained and is composed mainly of quartz, which also replaces certain particles. Yellow to iron brown clays rim clasts, fill vesicles and also partially replace glass. Glass of pumice is replaced by large laumontite and albite crystals (up to 2 mm) which enclose several vesicles. In these pumice clasts, clays have higher interference colours. All plagioclase is very dirty and albitized. A great number of late fractures occur and penetrate all alteration minerals, primary clasts and crystal clasts. Iron

oxides and dark brown clays rim clasts and occur in fractures, which also penetrate laumontite crystals. Sample 09LM010, occurring higher in the same lapilli tuff bed, contains fine-grained zones (crystals < 5 µm), where albite and quartz are concentrated and coarser zones (laumontite to 1.5 mm), where laumontite is concentrated. Large laumontite crystals contain small euhedral albite crystals (10-100 µm). All feldspar crystal clasts and phenocrysts are albitized. Clays are common, are iron brown and coarse crystalline. The distribution of clays, quartz and fluid inclusions in laumontite remind of relatively large vesicles in pumice, but also to round mordenite aggregates, which are all replaced. Reddish iron oxides occur mainly along cracks which also penetrate laumontite crystals. Laumontite has undulous extinction. Sample 09LM011, occurring in the upper part of the same lapilli tuff bed, contains more clay minerals compared to sample 09LM010. Some clasts, which are highly crystalline, are not effected by alteration. Clays are yellow brown and can be very fine-grained or can form coarse bundles (up to 40 µm). Clays mainly fill vesicles but some particles are completely or for a major part replaced by clay minerals. Laumontite mainly replaces glass in pumice together with clay minerals and also occurs in voids between clasts. Dark brown iron oxides occur at particle rims, cracks and in porous zones, formed as a late phase. All plagioclase phenocrysts in pumice and crystal clasts are dirty and albitized. Clay minerals in pumice delineate forms which were probably round vesicles, while spherically aligned fluid inclusions possibly indicate replaced spherical mordenite aggregates. Albite occurs in albitized plagioclase crystal clasts or together with quartz in volcanic clasts. Sample 06LM104, which is underlying the next almeja sequence, was probably a crystal-glass tuff, but very little of its original structure has been preserved. The sample is composed of an interlocking pattern of albite, quartz and laumontite. Pumice clasts are mainly replaced by laumontite. Red iron oxides and reddish brown clay minerals occur, but are the last minerals being formed, filling remaining voids. Anatase is common. The sample has a


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“mottled” appearance, because of the occurrence of zones where dark iron oxides are concentrated and zones where laumontite is concentrated. Sample 06LM106 is from a second almeja sequence. Clays, mostly dark brown but also greenish (celadonite and chlorite), are common in the sample and are relatively fine-grained. They rim clast, fill voids and vesicles and replace the major part of some particles. Mordenite is visible in voids between particles and replacing glass in pumice, but is replaced by heu-type zeolites and stilbite. Only 3% of remaining mordenite is detected by XRD. Heu-type zeolite and stilbite (up to 2 mm) crystals are particularly large in pumice with larger round vesicles, where they enclose several vesicles. Other pumice and the fine matrix of the sample seem to be replaced mainly by fine-crystalline quartz. Plagioclase phenocrysts are altered, but not albitized. Sample 06LM105 is a reddish clast occurring in sample 06LM105. Its matrix is composed of fine-grained quartz and red iron oxides. Some clast are completely altered to green clays (celadonite). The fine-grained sample 09LM012 contains a fine altered glassy matrix composed of iron brown clays, iron oxides and quartz. Laumontite occurs in zones, where it replaces glass shards. This zonal distribution gives a “mottled” appearance to the rocks. Iron oxides occur in cracks, more or less parallel to bedding. Sample 09LM013 of a next almeja sequence, contains a high amount of fine-grained spherical mordenite aggregates (5-20 µm), which can form larger aggregates (up to 80 µm) in vesicles, mainly occurring around phenocrysts in pumice. The alteration in the majority of the sample is fine-grained (< 10 µm). Clays are mostly green but iron brown well crystalline clays also occur. Green clays rim and fill vesicles, line particles and seem to be common in layer parallel dissolution zones, where they can be associated with iron oxides, for example on top or below crystal clasts. In these cases, they not necessarily form before zeolites. In some areas mordenite is replaced by heu-type zeolites and stilbite. Sample 09LM014 occurs higher in the same layer and has a similar alteration as the

underlying sample. Mordenite, occurring in voids, forms spherical aggregates, which can be large (up to 100 µm) in size and which are typically rimmed by impurities. Next to mordenite, quartz is the main alteration mineral. Most pumice is replaced by fine crystalline mordenite (10-50 µm) and quartz (< 10 µm). Compacted pumice is altered to brownish green clays, which are more common compared to sample 09LM013. Iron oxides occur along bedding parallel dissolution fronts. Sample 09LM015, from the base of the overlying bed, has a similar early mordenite formation, but all mordenite has been replaced by large stilbite and heu-type zeolite crystals (up to 2 mm). No remaining mordenite is detected by XRD. Spherical mordenite aggregate ghosts remain visible in these crystals (30-100 µm), and several aggregates can occur in one crystal. Stilbite is concentrated in pumice clasts, where it forms large interlocking and sometimes typically twinned crystals. Smaller euhedral crystals (50-200 µm) are enclosed in larger crystals, which enclose entire pumice clasts. Quartz crystallites preserve vesicle rims. In other zones a fine-crystalline mosaic of alteration minerals occurs. Both iron brown, bluish green (celadonite) and green clays occur, but are not very common. Some greenish clays (chlorite) occur along dissolution fronts aligned along layering. Sample 09LM016 occurs higher in the same bed. Dark brown to bluish green (celadonite) to green (chlorite) clay minerals rim and fill vesicles of pumice clasts. Quartz also rims vesicles and replaces glass. In some vesicles, it can be seen that greenish blue clays form first, rimming vesicles, that brownish clays form later and that greenish (chloritic) clays are the latest to form. Mordenite mainly fills vesicles in pumice and also replaces glass. Heu-type zeolites are formed after mordenite, and sometimes replace it. Some green clay minerals occur in pumice clasts, which are strongly compacted along layering. Some particles are mainly altered to heu-type zeolites, while others are mainly altered to mordenite. Heu-type zeolites seem to be associated with pumice with larger vesicles which contain mainly brownish clays. Pumice with finer, more tubular vesicles tends to


93

contain more quartz and mordenite and less brownish clays. Sample 09LM017 from the upper part of the next layer contains zones of very fine-grained alteration, which are mainly composed of quartz. Round spherical forms in these zones remind of spherical mordenite aggregates of more or less 100 µm in size. Some of these spheres were definitely vesicles in pumice, but most are equally sized, perfectly round and too close together to be vesicles, and were thus probably mordenite aggregates. Other zones of the sample are replaced by large euhedral laumontite. Similar round shapes, formed by quartz and clay minerals, remind of pumice. Euhedral anatase is common. Clays are yellow brown and have relatively high interference colours. Dissolution occurs at rims of particles and iron oxides are concentrated along these rims. This dissolution is not only along layering, but also perpendicular to layering and penetrates laumontite crystals. All feldspars are albitized. Sample 09LM018 contains a matrix of microcrystalline laumontite, albite and quartz. Other zones contain larger (~ 200 µm) crystals and are composed of laumontite, stilbite and calcite, which typically have a puzzle shaped interlocking form. Quartz is always very fine crystalline (< 5 µm) and spread through the laumontite crystals. In some cases, shapes which remind of round vesicle outlines or spherical shapes of mordenite aggregates (~ 50 µm), can be recognized, because they are delineated by fine quartz crystals, filled with clay minerals, or because calcite and laumontite crystals are formed in these round shapes. In most cases, laumontite does not form large crystals enclosing several vesicles, as is seen in previous samples, but crystals which are more interlocking in form and which could be pseudomorphs after heu-type zeolites or stilbite. Clays are iron brown or green and well crystalline. Albite occurs as smaller euhedral crystals (10-50 µm) in laumontite and stilbite. Sample 09LM019, occurring higher in the same layer, is composed mainly of very fine-grained (< 10 µm) alteration minerals with low interference colours. From XRD it is derived that these minerals are mainly quartz, heu-type zeolites and mordenite. In some zones,

alteration minerals are coarser (20 – 50 µm, 100 µm for mordenite aggregates) and mainly brown but also greenish clays occur. Greenish clays also occur at dissolution fronts around phenocrysts. Iron oxides occur in stylolites parallel to bedding. Mordenite forms radiating bundles replacing glass and also fills vesicles in pumice. Calcite occurs in round forms, replacing mordenite (aggregates of ~ 50 - 100 µm) or is filling vesicles. It also seems to form pseudomorphs after heu-type zeolites. Euhedral pyrite forms in some clay-altered pumice, but is overgrown by Fe oxides. Sample 09LM020 from the layer above, contains a high amount of iron brown clays, which rim vesicles, fill vesicles but also replace glass in pumice. Some particles are replaced completely by clays. In some areas, even the entire matrix between crystal clasts is replaced by clay minerals. Clays can have high interference colours. Laumontite replaces glass or possibly clay minerals and form relatively large crystals (up to 400 µm), but smaller compared to the samples below. Its shape is similar to the shape of heu-type zeolites, possibly it replaces them. In other regions the shape of laumontite is more interlocking, which could be because of a replacement of earlier heu-type zeolites. Laumontites with spherical extinction could be replacing mordenite. Other zones of the sample 09LM020 are replaced by very fine-grained quartz. Pressure dissolution of pumice around large quartz crystal clasts concentrates brown clays. A high amount of plagioclase crystal clasts is present. All are dirty and completely altered. Quartz crystal clasts seem to be altered at their rims. Sample 09LM021 contains very fine-grained alteration minerals with low birefringence. According to XRD, these minerals are mainly mordenite, quartz and clay minerals. Greenish to brownish clays rim clasts and fill vesicles. They have relatively high interference colours. Bedding parallel stylolites occur. Sample 09LM022 contains a high amount of quartz. Laumontite occurs in veins and is concentrated in zones, where it replaces glass, giving a mottled appearance to the rocks. In other zones, reddish iron oxides are concentrated. Most alteration minerals are very fine-grained (< 10 µm), only laumontite


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crystals, enclosing hundreds of glass shards and thousands of fine quartz crystallites, can be very large (up to 2 mm). Sample 09LM023 contains iron brown clays which rim particles and fill vesicles in pumice. Some zones of the sample contain very fine-grained alteration minerals, mainly mordenite and quartz. In other zones, where pumice has larger vesicles, commonly near crystal clasts, larger spherical mordenite aggregates crystallise (up to 150 µm). In some voids radial bundles of coarse clays, with high interference colours crystallise (up to 150 µm). Calcite also fills large voids in these locations. Some clasts are replaced by mainly brownish clays and calcite, which can form large crystals (up to 1mm). Next to mordenite, another mineral (heu-type zeolites or albite?) crystallizes in spherical forms. Heu-type zeolites replace glass as euhedral intergrown crystals.


Sample 09LM024 contains a high amount of crystal clasts and crystalline particles which are only partially affected by alteration. Plagioclase is mainly affected by clay alteration and can be partially albitized. The high amount of quartz detected in the sample by XRD, is partially due to the large amount of quartz crystal clasts. Greenish to dark brown clays and Fe-oxides rim particles and occur in the matrix together with fine crystalline quartz. Crystal clasts and volcanic clasts seem to be fractured in situ. Mordenite forms relatively large (200 µm is common), not very dense aggregates in pumice but is completely replaced by heu-type zeolites, no remaining mordenite is found in XRD. Heu-type zeolites form interlocking anhedral to subhedral crystals. Some clays form along cleavage planes of heu-type zeolites. Laumontite occurs mainly in pumice, where it replaces glass as large crystals enclosing large parts of single pumice clasts. Heu-type zeolites and laumontite do not occur together, but in different clasts, although in some cases possible evidence of heu-type zeolite replacement by laumontite can be observed. In sample 09LM025, occurring higher in the same layer, quartz and greenish clays are the main alteration minerals. All alteration

minerals are very fine crystalline. Mordenite forms small radial aggregates. Some zones of the sample are completely replaced by mordenite, in other zones quartz is more concentrated. Mordenite spheres are very fine in tubular pumice and in fine-grained zones in the matrix (< 20 µm), but in larger vesicles they can form larger bundles (50-200 µm). Irregular cracks penetrate through the rock and are filled with iron oxides. Sample 09LM026, occurring higher in the same layer, has a similar alteration as 09LM025. Alteration minerals are typically very fine-grained (<20 to 30 µm), although in more porous zones they can be larger. Clays are mainly concentrated along bedding parallel stylolites which develop in tubular pumice oriented in this direction. Sample 09LM027 contains clays with relatively high interference colours, which rim particles, compose part of the matrix of the rocks, fill vesicles, replace glass in pumice and form along cracks. Remains of mordenite aggregates can be observed in pumice, but all mordenite has been replaced by laumontite, which forms large crystals (up to 1 mm) which enclose small euhedral albite crystals (50-100 µm). Laumontite also forms spherical aggregates and in some zones smaller (40-60 µm) crystals. Quartz occurs as very small crystallites. Plagioclase crystal are common in the sample and are all replaced by albite. Calcite grows in cracks, mainly in pyroxenes. Sample 09LM028 contains a high amount of brownish clay minerals, which are generally fine crystalline (< 5 µm). They mainly fill and rim vesicles in tubular pumice. More crystalline clays rim particles and cracks. Mordenite occurs in the fine matrix of the sample, replaces glass in tubular pumice and forms large spherical aggregates (~ 100 µm) near phenocrysts. Heu-type zeolites replace pumice clasts as euhedral crystals and are nicely visible in pumice with larger vesicles, where they crystallise after mordenite. Laumontite is concentrated in zones where it replace pumices as “puzzle formed” crystals with undulous extinction. Tiny crystals of mainly quartz and minor albite are included in the larger laumontite crystals (mainly puzzle shaped crystals occurring in aggregates up to 500 µm in size). The shape of some laumontite


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crystals reminds of round mordenite aggregates, which were probably replaced by laumontite. The Ca-rich centre of plagioclase is replaced by calcite while the more Na-rich rims are unaltered and no albitization of plagioclase crystal clasts occurs. Some large spherulites occur, but these are probably formed by high temperature devitrification. In sample 06LM108 greenish to brownish clays rim pumice and fill vesicles. Mordenite occurs as very fine to large spherical aggregates filling empty spaces and replacing tubular pumice. Heu-type zeolites replace glass. Alteration minerals are mostly fine crystalline (<10µm), except in some larger vesicles or in the vicinity of phenocrysts or crystal clasts. Plagioclase crystal clasts can be unaltered or can be partially altered to clays, but are not albitized. Sample 09LM029 probably originally contained a high amount fine-grained spherical mordenite aggregates (spheres of ~100µm), but all are replaced by large to moderate sized laumontite (100 µm to 1 mm) and albite or microcrystalline quartz and albite. Laumontite crystals can have a puzzle shape and/or undulous extinction, which could reflect recrystallisation from smaller mordenite aggregates and heu-type zeolite crystals (analogue sample 09LM028). Clays are brownish with relatively high interference colours. Clays mainly occur in strongly compacted pumice particles. Compaction and pressure dissolution occurred in the sample. Dissolution rims can be seen at edges of particles. The clays now present in the sample, could be recrystallised from primary clays, because they seem to be redistributed along dissolution/compaction fronts. In sample 09LM030 alteration minerals are very fine-grained. Clays and quartz rim glass shards and occur between shards as fine spherical aggregates, while mordenite nucleates from the shard rims inwards. Sample 06LM109 is pervasively altered, no primary structures remain. Laumontite is the main alteration mineral, forming very large crystals (1 mm or bigger) and enclosing small quartz crystallites (< 10 µm) and small euhedral albites (40-80 µm). Calcite forms large twinned crystals (0.5-2 mm), which

enclose smaller albite and quartz crystals. In other zones alteration minerals are smaller, a mosaic of quartz, feldspar and laumontite occurs. Anatase and reddish iron oxides form relatively large euhedral crystals and smaller anhedral crystals (80µm). Clays are rare, some brownish clays occur. Crystal clasts are strongly fractured in situ and plagioclase crystal clasts are albitized. Round edges of calcite crystals remind of mordenite aggregates. Sample 06LM110 is similar in appearance as sample 06LM109. Laumontite forms very large crystals (1 mm) which overgrow all clasts and other alteration minerals. In other zones crystals are finer grained and interlocking (puzzle of laumontite and quartz). Brown clays are formed in remaining voids and fractures and many are formed along laumontite cleavages. Calcite also forms in cracks. Some clasts are altered to greenish C/S clays, which crystallise in spherical aggregates with high interference colours. Plagioclase is albitized. Some spherulitic structures occur, but these were formed by high-T devitrification in pumice. Sample 09LM032 contains more clay minerals compared to the underlying samples. Clasts are rimmed by iron brown clays, some are entirely replaced by brown clays. In other areas, all clasts are replaced by laumontite and albite. All plagioclase is albitized. Small euhedral albites occur in larger albite and laumontite crystals. Some small quartz crystals are aligned along semi-rounded primary structures, which could have been vesicles or spherical mordenite aggregates (~200 µm). Late illitic clays form in cracks.


In sample 09LM033, a high amount of clays is present. Brown clays rim particles and vesicles and partially replace glass. Some particles are entirely replaced by brown clays, or by brown clays and quartz. Some particles contain vesicles filled with brown clays and are replaced by large albite or laumontite crystals (up to 500 µm). In other zones, more fine-grained albite and quartz occur (<10 µm). All plagioclase is albitized. Larger laumontite and albite enclose smaller euhedral albite crystals.


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Iron oxides occur in cracks and voids. Some round spheres (50-100 µm) delineated by fluid inclusions occurring in laumontite crystals, or shapes of laumontite crystal surfaces evidence a possible early mordenite crystallisation. Most volcanic clasts of sample 06LM113 are crystalline and not, or only partially altered. Clays mainly fill vesicles, but also replace some particles almost entirely. Greenish clays (chlorite) form after brownish clays. Most clays have high interference colours and can be coarse-grained (several µm). Some late clay minerals occur in cracks. Clays seem to differ in different particles and in the matrix of the rocks. Laumontite, albite and stilbite all replace glass in pumice. They form large crystals which enclose several vesicles (up to 500 µm). Stilbite crystals can be twinned. Some particles are partially replaced by laumontite and partially by stilbite. Both minerals also fill voids (crystals up to 1 mm) between clasts or this could be locations where they replace a fine interstitial matrix. In other locations, a fine matrix is observed, which is mainly altered to fine crystalline quartz and clay minerals. In laumontite, some spherical forms remain which could have been mordenite (100 µm). Calcite forms small irregular veins which crosscut laumontite. Sample 06LM114 contains relatively much clay minerals which mainly fill vesicles and also partially replace glass. Voids are filled with very large (up to 500 µm) spherical mordenite aggregates, but these aggregates are replaced by heu-type zeolites and quartz. As quartz replaces some of these spherical aggregates, some of them can have been opal-CT and not mordenite. Heu-type zeolite crystal aggregates can preserve the spherical shape of mordenite aggregates. In schlacke, which have a crystalline matrix, heu-type zeolites and spherical bundles of C/S fill vesicles (C/S crystal size up to 20 µm). In pumice, yellow Fe-clays rim and fill vesicles and heu-type zeolites replace glass. Other clasts and the matrix are mainly replaced by fine-grained quartz, heu-type zeolites and clay minerals. Anatase only occurs in certain particles, where it occurs in the outer rim, formed before zeolites. In sample 09LM035 iron brownish clays rim pumice and also fill vesicles. Fine-grained

laumontite, albite and quartz replace the glass in most clasts (~20 µm), while brown clays fill vesicles. In other regions, laumontite is coarser grained (up to 500 µm). All plagioclase occurring in clasts is albitized. Large laumontite also occurs between the clasts, but undulous extinction can possibly indicate that at least some of these crystals replace earlier formed alteration minerals. Iron oxides occur in cracks. Sample 09LM036 has a fine matrix, which was originally altered to mordenite and later recrystallised to heu-type zeolites. Compacted pumice is rimmed by iron brown to greenish clays and fine-grained silica and radial mordenite bundles replace glass (10-20 µm). Almost all mordenite is replaced by heu-type zeolites, but mordenite ghosts are present because small inclusions of clays, iron oxides and quartz remain around the former aggregates. A second type of pumice, with larger round vesicles, is rimmed and its vesicles are filled by brownish clays, while heu-type zeolites replace glass (50-100 µm). Other zones are replaced by fine-crystalline quartz and clay minerals. Some zones are recrystallised to stilbite. Feldspars are not albitized but are partially replaced by calcite, clay minerals and laumontite. A fracturation phase occurred through crystals and matrix. In sample 06LM115, alteration of tubular pumice is generally very fine-grained (10-20 µm). Alteration minerals are mordenite, quartz, heu-type zeolites and greenish clay minerals. Mordenite occurs in vesicles and fills interstitial voids with large spherical aggregates (100 µm). In some pumice particles, vesicles are rimmed by greenish clays and silica, while mordenite crystallises from the rims. Heu-type zeolites are formed after mordenite, partially replace it and crystallise central in vesicles. In the interstitial voids between particles, mordenite crystallises outwards from the particles and heu-type zeolites overgrow mordenite more central in the voids. In some pumice, heu-type zeolites crystallise directly on clays and no mordenite occurs. Calcite forms as a late phase in cracks. Iron oxides form where clasts are affected by dissolution and also fill late cracks. In sample 09LM038 most alteration minerals are fine-grained (<10 µm), with the major


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alteration minerals being quartz, mordenite and clay minerals. Around large phenocrysts in pumice, where vesicles are unstretched, larger alteration minerals can crystallise (up to 100µm). Quartz and albite possibly crystallise in some fine tubular pumice. Brown clays are concentrated in certain zones, where they replace the majority of the pumice. In sample 06LM116, alteration minerals are also fine-grained (< 30 µm). The main alteration minerals are quartz and spherical mordenite aggregates, which replaces glass and also fill voids and vesicles. Fine-grained green clays (chlorite) are concentrated in certain zones, fill larger unstretched vesicles and also occur in cracks. Part of the mordenite crystals are recrystallised to heu-type zeolites and heu-type zeolites also occur in pumice with larger unstretched vesicles. Sample 09LM039 contains larger alteration minerals (100-300 µm) compared to the underlaying samples. It contains dark brown clays which rim particle and vesicle outlines, but others seem to have also a more random distribution, possibly because of recrystallisation of primary clay minerals or other minerals which caused a redistribution of clay minerals. Mordenite replaces glass, but is replaced by heu-type zeolites and stilbite. Stilbite forms small twinned crystals which are enclosed in larger crystals. Fine quartz crystallites are spread through the sample (10 µm). In sample 09LM042, pumice is rimmed by quite common brownish to greenish clays, which also fill vesicles and replace some particles entirely. These particles seem to be stretched/compacted to such a high degree, that no remaining vesicles occur. Mordenite occurs as spherical aggregates in pumice with irregular vesicles and in voids between the particles. Quartz crystallises after mordenite in the centre of voids. In other regions alteration minerals are very fine crystalline. In other pumice particles, heu-type zeolites replace glass, while clay minerals fill vesicles and no mordenite is present. In other pumice heu-type zeolites and mordenite occur together, with heu-type zeolites forming after mordenite. Calcite occurs as large twinned crystals. Plagioclase can be albitized or partially altered to clay minerals. Late fractures cross-cut

spherical mordenite, heu-type zeolites and plagioclase. Mordenite seems to nucleate more from quartz, while heu-type zeolites nucleate mainly from brownish clay minerals.

9.3.4 Upper part of the lower unit

In the coarse part of sample 06LM118, greenish and brownish clays form a thin film around all particles and fill vesicles in pumice. Almost all zeolites have a spherical form and nucleate from the outer rim of glassy particles towards their centre. The shape of these aggregates is somewhat different from typical mordenite aggregates in the underlying samples, individual crystals are thicker. It is not always clear if these aggregates are composed of mordenite, heu-type zeolites, or mordenite replaced by heu-type zeolites. Only 5% of mordenite is found in XRD, so probably most of these aggregates are heu-type zeolites. Heu-type zeolites crystallise after mordenite, central in voids. Some plagioclase crystal clasts are relatively fresh, or are only partially altered, others are more altered, albitized, or partially replaced by zeolites, clay minerals and calcite. The fine-grained part contains fine alteration minerals and more quartz and calcite. In sample 06LM123, alteration minerals are very fine-grained and mainly quartz, heu-type zeolites and minor mordenite occur. Glass shards are completely replaced by zeolites, while quartz is concentrated in the matrix of the sample. Fine-grained red iron oxides occur spread through the rocks. Laumontite veins cross-cut the sample. Iron oxides are concentrated in zones. In sample 06LM178, yellow clays seem to replace the majority of the sample. Glass is replaced by zeolites with low interference colours. Plagioclase crystal clasts are very fresh in comparison to the underlying rocks of C1a and C1b, where plagioclase is very dusty and where it is partially replaced by clay minerals or albitized. Plagioclase crystal clasts can be heavily fractured, clay minerals occur in cracks. 50% of the sample is composed of heu-type zeolites, as detected by XRD, but all heu-type zeolites are very fine-crystalline and therefore difficult to observe under the


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microscope. The amount of quartz is also very low (6%). Sample 06LM176 is heavily compacted and fractured. Some zones are composed of very dark brown to orange brown to red and some green clay minerals. Clay minerals replace glass, some clasts are entirely altered to clay minerals. Reddish iron oxides occur in clay-rich zones and along cracks. Other zones are composed of fine-crystalline heu-type zeolites. Some zones are entirely replaced by heu-type zeolites and contain no clays. Heu-type zeolites crystallise from particle rims towards the centre of particles. This mode of crystallisation is different from the samples of C1b, where heu-type zeolites crystals are more randomly oriented. The quartz content of the sample is very low. Early mordenite crystallisation is possible, but mordenite is replaced, as it is not detected by XRD. Sample 06LM074 is composed mainly of dark brown clay minerals and heu-type zeolites. Clay minerals fill vesicles and partially replace glass in pumice. Possibly the more permeable zones (pumice with larger vesicles) are preferentially replaced by clay minerals, while the finer zones (smaller, more impermeable pumice clasts, fine matrix and glass), are replaced by heu-type zeolites. The quartz content is very low. Heu-type zeolites crystallise inwards from particle and vesicle rims. Heu-type zeolite can be euhedral, radial or anhedral, blocky, as is typical for all coarser and clay rich samples of this part (06LM118 and above). Plagioclase phenocrysts are relatively fresh. In sample 06LM079, dark iron brown clay minerals rim particles and fill vesicles. Some clay minerals occur in cracks. Some greenish coarser clay minerals (up to 60 µm) form central in vesicles. Glass in pumice is replaced by heu-type zeolites (50-100 µm), which are relatively coarse and more randomly oriented, not crystallising from particle rims or vesicle rims. Anhedral analcime (100-300 µm) fills vesicles in clasts, which are mainly altered to brownish clays, fills vesicles in schlacke or occurs central in voids, where it overgrows heu-type zeolites. Irregular fine calcite veins are common. In some of the heu-type zeolite crystals dusty spherical rims are observed, which can have been mordenite aggregates

which are now recrystallised. This can also explain the spherical shape in which heu-type zeolite crystals grow. Analcime also possibly replaces mordenite aggregates in some pumice. Sample 06LM080 is a red clast occurring in sample 06LM079. It is composed of spherically formed quartz, which contains calcite in its centre. It is not know how these structures were formed. The reddish colour is caused by iron oxides. Using X-ray diffraction, apophyllite was identified in the sample. Sample 06LM082 is composed completely of large euhedral twinned stilbite laths (1-1.5 mm), no original structures are preserved. Calcite and quartz are microcrystalline and are overgrown by the stilbite laths. Clay minerals are dark brown and irregularly spread over the sample. In sample 06LM085, most of the pumice is altered to puzzle shaped anhedral heu-type zeolites. Quartz and clay minerals form small crystallites. Round forms of some heu-type zeolite crystals remind of mordenite spheres. Stilbite forms blocky and twinned crystals and also replaces plagioclase. In other zones of the sample, green and brown clays replace pumice. These zones are heavily compacted and stylolitized. Feldspars are altered. Calcite forms large twinned crystals (200-500 µm), which are corroded at their edges. Sample 06LM087 is composed of fine laumontite, quartz and calcite, which form a fine interlocking irregular pattern. Especially calcite is very common in the sample. Cracks are easily identified in the sample, are full of iron oxides and calcite is concentrated in and around them. In some zones calcite forms larger twinned crystals. As is observed in other samples, sample 06LM086 contains certain zones which are altered to clay minerals and other zones which are altered to zeolites. Clay minerals are iron brown and green in colour, and the zones where they occur can be strongly compacted. Zeolitic zones generally contain very fine crystalline zeolites (< 10 µm). In some larger vesicles in pumice clasts or voids near crystal clasts or phenocrysts, zeolites can crystallise larger (50µm). In pumice, clays can replace the majority of the glass, can fill vesicles or can be rare to absent. Heu-type zeolites and/or


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mordenite replace glass, with heu-type zeolites crystallising after mordenite. Mordenite crystallises as spherical bundles nucleating from small quartz aggregates, which occur at the outer rims of particles.


Sample 09LM052 is altered to brownish clays, heu-type zeolites and mordenite. Clays are quite common, mostly dark brown, but can be greenish (celadonite). Greenish clay minerals occur centrally in pumice clasts and not at their rims and always crystallise before brown clay minerals. Brownish clay minerals rim particles, fill vesicles in pumice, replace glass of some particles and occur in voids and cracks. Both spherical mordenite aggregates and heu-type zeolites replace glass in pumice (30-100 µm). Mordenite forms before heu-type zeolites and nucleates on fine-crystalline quartz. All plagioclase crystal clasts ad phenocrysts are fresh. Calcite occurs in certain zones, its shape reminds of the shape of radial mordenite aggregates. The quartz content in the rocks is relatively low. In sample 09LM053, a more clear distinction can be made between zones of clay alteration and zones of zeolitic alteration. Clay minerals are iron brown to brownish green or green. Zones rich in clays generally contain pumice, which can be strongly compacted. Where strong compaction occurs, greenish (C/S or chloritic) clays occur. Zeolitic zones contain few clay minerals and are composed mainly of spherical mordenite aggregates (20-100 µm). A larger spread in the size of mordenite aggregates occurs compared to the previous sample and more fine-grained aggregates occur. Mordenite is also more common compared to the previous sample. In voids, an evolution can be seen from crystallisation of spherical mordenite aggregates to spherical heu-type zeolite aggregates with thicker crystals to more randomly oriented heu-type zeolites with larger crystals central in the voids. Clays have higher interference colours compared to the underlying sample and greenish (celadonite) clays are more common. When occurring, celadonite crystallises before iron brown clays, as it rims vesicles in pumice, and brownish clays occur more central in

vesicles. Plagioclase is moderately altered, the quartz content is relatively low. As the underlying sample, sample 09LM054 contains well defined zones with more clayey and more zeolitic alteration. Clay minerals are iron brown to greenish brown, with greenish clay minerals mainly concentrating in compacted pumice zones. Zeolitic alteration is similar as in the underlying sample, but quartz and mordenite are more common compared to heu-type zeolites. Mordenite typically nucleates on quartz, while heu-type zeolites nucleate more on brownish clays. In zones where both zeolites occur, which are mostly zones with a higher porosity, heu-type zeolites can nucleate on mordenite. Zones with low amounts of clay thus tend to contain less heu-type zeolites, unless heu-type zeolites crystallise on mordenite if any remaining space is left. Zones with more brownish clays, which are also porous (large vesicles), tend to contain more heu-type zeolites. Sample 09LM054 seems to be less porous than the underlying sample, it also contains less brownish clays. Zeolites in fine zones are typically 10µm, while in coarser zones 50-100 µm. In sample 09LM055 clast outlines are more easily distinguished compared to the underlying samples. (more volcanic fragments, probably separate pyroclastic flow deposit). Some clasts are more argillitized, while in others, clay minerals fill vesicles while zeolites replace glass. Clays are iron brown to brownish green to green in colour. Zeolitic alteration is very similar compared to the underlying samples. The size of zeolite crystals is 20-50 µm. In contradiction to the underlying samples, brownish clays are not common in sample 09LM056, while greenish clays (celadonite) are common. Zeolitic alteration is similar as in underlying sequences, with mordenite dominating. The sample is composed mainly of fine tubular pumice. The size of zeolite crystals is generally smaller than 10 µm. Sample 06LM090 is strongly compacted, with brownish clays and iron oxides formed mainly in compaction/dissolution fronts and in rare very fine vesicles. Mordenite greatly dominates over heu-type zeolites. The size of alteration minerals is smaller than 10 µm.


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In sample 09LM066, alteration minerals are all very fine-grained (< 10 µm). Clay minerals are not common and occur mainly along dissolution fronts and fill vesicles in some coarser pumice clasts. Most of the sample is altered to very fine-grained mordenite aggregates (<10µm).

9.4 Alteration in the upper unit of

the Cayo Formation

9.4.1 The lower part of the upper unit

The base of the upper unit

The fine-grained rocks at the base of the upper unit of the Cayo Formation have a high content in calcite, quartz and clay minerals. Heu-type zeolites only occur as glass replacement and filling voids in microorganisms, but are not present in the matrix of the rocks. Greenish clay minerals replace some glassy particles. A remarked difference with the lower unit of the Cayo Formation is the abrupt decrease in the mordenite content at the base of the upper unit. Mordenite only occurs in amounts lower than 5% in the basal part of the upper unit and is rare to absent higher in the section.

Lower part

Fine-grained tuffs occurring higher in C2a, are altered to brownish and greenish clay minerals and heu-type zeolites, have low quartz contents and can contain some mordenite fibres (06LM145, 148). The coarser lapilli tuffs in the lower part of C2a can be altered to heu-type zeolites, can have a mixed heu-type zeolite – laumontite alteration, or can have a laumontite alteration. All rocks have a very low quartz content, except the rocks containing laumontite, which have a low to moderate quartz content (<15%).

Lapilli tuffs with heulandite-type zeolite

alteration

Coarse to relatively fine-grained rocks with a heu-type zeolite alteration (samples 06LM150–151), contain a very low amount of quartz (<5%), a high amount of plagioclase (25–

30%), a moderate to high amount of clay minerals (10–45%) and a moderate amount of augite (8–10%). Feldspars are altered and can be albitized. Calcite and iron brown to greenish brown clays, with low interference colours, rim particles and pumice. Pumice is compacted and dissolved, greenish C/S clays with higher interference colours and relatively fine crystalline subhedral to anhedral heu-type zeolites replace glass in pumice and fill voids. Some mordenite needles can be observed. Brownish clays and calcite form as late phases in cracks.

Lapilli tuffs with co-occurrence of heulandite-type zeolite and laumontite

alteration

Sample 06LM129 occurs in the uppermost beds of the lower unit of the Cayo Formation, but has a similar alteration as the samples of this group and is therefore discussed here. The sample contains a fine matrix composed of fine crystalline alteration minerals, which are probably iron oxides, quartz, calcite and heu-type zeolites. Brownish clay minerals rim all particles, while greenish clay minerals only occur in clasts. Some particles are more argillitized than zeolitised. Some particles are entirely replaced by clay minerals, while calcite fills vesicles. Plagioclase is albitized or altered to laumontite, but not all plagioclase is altered. Heu-type zeolites and laumontite occur in different clasts. Celadonite occurs in some clasts. Using hot cathodoluminescence observations, the distribution of the alteration minerals can be observed more easily in the sample. Heu-type zeolites, which have a light bluish luminescence colour, replace glass shards in the matrix and replace glass in pumice clasts. The fine matrix is mainly replaced by quartz and clay minerals with kaki green to brown luminescence colours and these minerals also seem to replace and rim glass before heu-type zeolite crystallisation. Calcite, with orange luminescence colours, is present in the matrix, fills mainly voids, such as vesicles, but also replaces particles. Laumontite, with light green luminescence colours, replaces glass in particles, but occurs also in certain areas in the matrix. Authigenic albite, fluogreen in colour, forms fine-grained euhedral crystals.


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Sample 06LM146, probably of epiclastic origin, has a cryptocrystalline matrix, that is composed of clay minerals, quartz and calcite and that contains some glass fragments, which are replaced by heu-type zeolites. Calcite rims particles and is an important component of some particles (mainly schlacke) and is formed before clay minerals. Possibly some clay and calcite alteration occurred previous to the final deposition of the rocks. Early formed clay minerals are cryptocrystalline and precede the formation of large euhedral heu-type zeolites, which replace glass in pumice and fill empty spaces. The alteration is different in different particles. In some particles clays have higher interference colours, are coarser and laumontite and calcite occur as alteration minerals. Sample 06LM154 contains a high amount of brownish clay minerals which rim particles, rim and fill vesicles and replace pumice. No fine matrix is present, feldspar crystal clasts are albitized. Heu-type zeolite formation is preceded by the formation of spherical mordenite aggregates, but all mordenite is completely replaced by heu-type zeolites and laumontite. Some ghosts of mordenite aggregates can be observed in the large heu-type and laumontite crystals. Heu-type zeolites and laumontite replace glass in pumice and mainly laumontite and minor heu-type zeolites are common in large voids between the clasts, where they replace mordenite or an interstitial fine matrix. Schlacke and semi-crystalline effusive volcanic particles are mainly altered to clay minerals, while zeolites fill vesicles. Some pumice is somewhat compacted, primary clays are recrystallised to coarser clays with higher interference colours and anhedral and interlocking heu-type zeolites are replacing glass. In these particles it can also be observed that fine brownish clays are possibly recrystallised to coarser C/S clays with higher interference colours and that during this process the distribution of the clays was changed, while pumice compaction occurred. Heu-type zeolites form during this process. Other glassy particles are mainly altered to brownish clay minerals. In less compacted pumice, clays fill vesicles, while randomly oriented subhedral heu-type zeolites replace glass. Some late clays and calcite occur in cracks and are formed after heu-type zeolites.

Lapilli tuffs with laumontite alteration

In sample 06LM149, laumontite is the only zeolite mineral present. The sample contains a high amount of clay minerals, plagioclase (21%) and augite (12%). Primary clays are dark brown, fine-grained and with low interference colours. In many particles, such as schlacke, clay minerals are the main alteration minerals. Some pumice is compacted and primary clays are redistributed and recrystallised to coarser C/S clays with higher interference colours. In pumice clasts, clays rim and fill particles, while zeolites replace glass. Possibly early formed fine-grained zeolites are replaced by larger albite and laumontite crystals, although it is difficult to find proof for this. During the conversion of primary clays and zeolites, authigenic quartz (14% in the sample) was probably formed. Laumontite is found in all voids, is replacing pumice and is intergrown with calcite. Voids between particles can be very large and contained probably originally glassy particles, which were completely dissolved during alteration. Some remains of these particles can be observed by the shapes of clay aggregates occurring in the centre of these voids. In highly altered particles dusty shapes in laumontite crystals remind of clays which were rimming round vesicles but which were later dissolved or replaced by laumontite. Primary clays were dissolved to form C/S, which is intergrown with laumontite and calcite. In other particles, primary clays remain and the alteration did not proceed to the higher grade alteration. Anatase occurs as an alteration mineral in pumice. In sample 06LM153, a high amount of mordenite and possibly heu-type zeolite ghosts are present, but no remains of these minerals can be detected in the XRD pattern. Needle-like forms show the presence of early mordenite and some shapes (at a high magnification) remind of heu-type zeolites, but all these minerals are replaced. Laumontite is the main alteration mineral. It occurs as large euhedral crystals between particles, and as large crystals replacing pumice in which round vesicles ghost are formed by clay minerals, although these minerals can be replaced afterwards. Primary clays rim vesicles, are fine-grained and have low interference colours. These clays are the main alteration minerals in (semi-) crystalline clasts. Some clays are


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coarser and have higher interference colours. Some euhedral authigenic albite is intergrown with these clays. Calcite occurs intergrown with laumontite or as a late phase.

The upper part

Tuffs Higher in the section, coarse lithologies are rare in outcrop, but probably, because of their low competence, they were easily weathered and removed by erosion. The fine-grained rocks in this part of the section (06LM157-161) are altered to fine-grained brownish clays, can contain early formed calcite and fine-grained heu-type zeolites which nucleate on these clay minerals.

Lapilli tuffs The only coarse sample, 06LM155, contains a high amount of clay minerals, augite and plagioclase. The sample contains light orange to brown cryptocrystalline clay minerals, rimming effusive volcanic clasts and pumice clasts and filling vesicles in pumice. Alternatively, reddish brown iron oxides rim particles. In some pumice, a sharp contact exists with bluish green clays, probably celadonite, which occurs more central in vesicles or which replaces glass. All clays are fine-grained, cryptocrystalline and with low interference colours. Heu-type zeolites are generally euhedral and clearly nucleate on these clay minerals and can grow spherically from their nucleation point, making their form and distribution different compared to the underlaying coarse beds, where they tend to be more randomly oriented and subhedral to anhedral. Early formed zeolites are smaller in size, with their long axis oriented from their nucleation point, while later formed zeolites are more randomly oriented, nucleate from earlier formed zeolites and fill all the remaining pore space. Some spherical forms could be ghosts of mordenite which crystallised before heu-type zeolites.

9.4.2 The middle part of the upper unit

Lapilli tuffs

Samples 06LM162, 166, 168 and 171 are coarse-grained and have a high augite content. Sample 06LM162 is a relatively fine-grained lapilli tuff. Primary clays are iron brown, occur in the pore space and rim and replace pumice and fill vesicles in pumice. Fine crystalline calcite is also early formed. Blue green celadonite can be clearly distinguished from these brownish clays, but occurs only in certain particles. Anhedral heu-type zeolites nucleate on clay minerals and form spherical or axiolitic structures. Later formed zeolites are larger, more euhedral and nucleate on earlier formed zeolites. Analcime is formed after heu-type zeolites and overgrows them. It forms large anhedral crystals in the remaining voids and also replaces plagioclase. A part of the primary clays is recrystallised to C/S, is well crystalline and has higher interference colours. This recrystallisation occurred during or after zeolite formation, as these clays also fill the remaining pore spaces and they seem to be redistributed during zeolite growth. Sample 06LM166 contains no quartz, has a high clay mineral content, a high augite content (22 %) and has a similar type of alteration as the underlaying sample. It contains only 4 percent of heu-type zeolites, while the analcime percentage is 28%. Sample 06LM168 contains a low amount of fine-grained iron brown clay minerals which rim pumice and line vesicles. Heu-type zeolites are blocky, large, euhedral and replace glass. In schlacke they fill vesicles and in some pumice clasts they replace clay minerals in vesicles. Euhedral calcite is intergrown with zeolites. In some vesicles coarse-grained clays occur. Some celadonite occurs in pumice. Sample 06LM171 contains poorly crystalline schlacke and pumice similar in appearance as the schlacke. Clasts are rimmed by yellow brown clay minerals and calcite, vesicles in pumice are filled with similar clays, while clays in the clasts are more reddish in colour. Clays have relatively high interference colours. Glass is replaced by anhedral to subhedral blocky and interlocking heu-type zeolites and these also fill voids. Analcime occurs as a later phase overgrowing heu-type zeolites.


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Feldspars are replaced by heu-type zeolites, calcite or analcime.

Tuffs

The fine-grained rocks generally contain early formed fine-crystalline calcite spread through the matrix and fine-crystalline brownish clay minerals and they can contain celadonite which is mainly concentrated in certain glassy particles. Heu-type zeolites are fine-grained, anhedral to subhedral and nucleate from the clays rimming the glass (samples 06LM163-165, 167, 169, 170, 172). Most alteration minerals are fine-grained, which makes it difficult to distinguish them optically. Secondary calcite occurs in layer parallel veins. When pumice is present, clays can be coarser in size and they can have higher interference colours. These clays seam to have been recrystallised from primary clays and are redistributed during the compaction of the pumice and the growth of zeolites.

9.4.3 The upper part of the upper unit

From sample 06LM169 and higher in the cross-section, quartz is found as a crystal clast in the rocks and the augite content is lower compared to the underlaying part. Volcanic schlacke are more common in the lapilli tuffs, argillitization is common and pervasive and heu-type zeolites are typically euhedral and axiolitic.

Lapilli tuffs

In sample 06LM182, the alteration differs clearly in the different clasts and in the matrix. The matrix of the sample is composed of plagioclase, Fe-Ti oxide crystal clasts, glass shards and small pumice clasts. The glassy particles in the matrix are rimmed by brownish clays and replaced by heu-type zeolites. In other areas, no fine matrix is present or it is completely replaced by large euhedral heu-type zeolites, which are crystallised from the particle rims, but which do not seem to be preceded in growth by clay minerals. Some clasts posses no zeolitisation and glass is replaced by fine-grained brown clays. Other particles are completely replaced by large

euhedral heu-type zeolites. Pumice clasts are rimmed by brown clays, while celadonite and heu-type zeolites replace the centre of the clasts. Other particles contain a high amount of calcite next to heu-type zeolites. Some clay minerals have high interference colours and in the central part of vesicles very coarse radial clay aggregates can occur. The alteration of sample 06LM180 is similar to sample 06LM182. Brownish and greenish clays (celadonite) rim particles and zeolites nucleate on these clays. In zones where a fine matrix occurs, heu-type zeolites are fine-grained and blocky, while in other zones, where heu-type zeolites seem to fill empty voids, they are larger in size and euhedral. These zones are too large to be voids, probably they were composed of a fine glassy matrix which was completely dissolved and replaced by alteration minerals. Late calcite crystals can be large in size, euhedral and fill the interstitial voids after zeolite crystallisation. Other finer calcite could be formed earlier in the matrix. Sample 06LM188 displays a large argillitisation of clasts. Clays are brownish yellow in colour. A very fine glassy matrix was present, which has been replaced by greenish to brownish clays and fine calcite and later by heu-type zeolites. In other zones, where the matrix was probably completely dissolved, or where no matrix was present, zeolites are larger in size and euhedral and nucleate from clay minerals at particle rims.

Tuffs

The fine-grained rocks of this part were composed mainly of silicic glass, as can be seen in the low augite content and the presence of quartz crystal clasts. The amount of authigenic quartz increases in these rocks. Samples 06LM175, 181, 184, 186, 190-194, 196 have a quartz content of 30-60%. They are very fine-grained and were composed mainly of fine glass shards. They are altered to fine crystalline quartz, generally low amounts of brownish clay minerals and contain relatively high amounts of calcite and heu-type zeolites.


104

The uppermost part of the Cayo

Formation

Lapilli tuffs In sample 06LM194, relatively fine pumice is replaced mainly by iron brown clays, which also rim particles. Heu-type zeolites occur as euhedral crystals in interstitial voids and as anhedral crystals in pumice and nucleate on clays. A high amount of schlacke clasts occurs, and these are mainly argillitized, while their zeolite content is low. Opal-CT probably nucleated before zeolites and mordenite possibly occurs. Sample 06LM198 is composed mainly of schlacke clasts, which are altered to orange brown to dark brown clays. Subhedral heu-type zeolites nucleate on these clays. Many particles contain mainly clays as alteration minerals. Analcime forms after heu-type zeolites, fills vesicles and replaces all plagioclase. Calcite forms as the last phase and occurs mainly in layer parallel cracks, which form around lithics and cross-cut zeolites. Samples 06LM201 and 06LM072 are similar as the underlying samples. They contain a high amount of augite crystal clasts and are highly argillitized. Sample 06LM067 is relatively fine and is altered to a light brown clay, which rims clasts and fills vesicles. Celadonite is common in this sample, occurring in pumice, where it fills vesicles and replaces glass. Some pumice particles are replaced by iron brown clays in one part, while celadonite replaces the other part. Heu-type zeolites form after clays and replace glass in pumice and occur in interstitial voids. They can be small and blocky to large and euhedral in form. Feldspars are all fresh. Calcite occurs as a late phase, mainly in layer parallel cracks. Probably some opal-CT was formed before heu-type zeolite formation. Sample 06LM070 was pervasively altered to iron brown clays, which are darker in colour in the clasts compared to the matrix. Clays in clasts are fine-grained and have low interference colours. Clays between the clasts are coarser and have higher interference colours. In some clasts, greenish clays, probably celadonite, occur. Heu-type zeolites

occur mainly between the particles, where they form large euhedral crystals which nucleate on particle rims. They also fill vesicles in crystalline volcanic particles. In other areas, heu-type zeolites are more blocky, more randomly oriented and they are not nucleating from particle rims only. It seems that they replace a fine matrix at these locations. After zeolite formation, euhedral calcite and coarse clays with high interference colours fill the remaining empty spaces. Quartz is absent (<1%). Sample 06LM071 contains much clays (50%), calcite (14%) and has a low amount of quartz (<2%). Sample 06LM061 contains brownish clays, rimming particles and vesicles, while greenish clays are limited to certain particles. Opal-CT clearly crystallised before heu-type zeolites, but is partly replaced by heu-type zeolites or quartz (10%). Heu-type zeolites are the main alteration minerals, replacing all glass in pumice and can be very small and anhedral to large and euhedral in form. Calcite occurs as a late phase in irregular veins.

Tuffs

The fine-grained tuffs 06LM199, 202, 63-64 have high quartz contents (30-60%). Sample 06LM068 is altered to brownish clays, greenish clays (celadonite) and heu-type zeolites. Opal-CT nucleates before zeolites. Calcite is formed before or during the formation of zeolites, as can be seen by heulandite veins cross-cutting calcite veins. It is not clear if celadonite nucleates before or after zeolite formation. Possibly some mordenite occurs. Sample 06LM060 is replaced by iron brown clays, calcite, heu-type zeolites and possibly analcime. Calcite occurs in cracks along layering.

Section 1 of the upper unit

Sample 06LM058 is a fine-grained tuff underlaying a coarse lapilli tuff sequence. The sample contains very fine-grained alteration minerals (<10 µm), mainly quartz (43%), minor irregularly shaped heu-type zeolites and some brownish clay minerals and opal–CT. Some angular glass shards are replaced by heu-type zeolites, but the majority of the more rounded clasts are altered to iron brown clays


105

and quartz. Quartz occurs mainly between the particles, filling the interstitial pores.

Sample 06LM057 from the basal part of the coarse lapilli tuff sequence, is pervasively altered to mainly brownish clays and minor heu-type zeolites. Greenish celadonite fills vesicles and replaces glass. Brown clays replace the main part of the glass. Opal–CT nucleates on brownish clays, forming spherical pyramidal crystals. Heu-type zeolites nucleate on opal–CT crystals, brownish clays or celadonite. They seem to replace opal–CT partially, and they take over the spherical shape of their nuclei. Heu-type zeolites are generally euhedral and are especially large in voids between particles. Probably they grow in spaces where pumice is dissolved. The quartz content is very low in the sample. Some late cracks cross-cut all pyrogenetic and authigenic phases and are rimmed by Fe-oxides. Sample 06LM054 is a fine tuff occurring higher in the same sequence, composed mainly of glass shards. The alteration minerals and their relative amounts are similar as in the underlying sample, but they are much finer grained. Yellowish brown clay minerals fill vesicles and replace glass partially. Heu-type zeolites replace the remaining glass. The quartz content is very low. Sample 06LM053 is a fine lapilli tuff occurring higher in the sequence, composed of pumice clasts and some effusive volcanic clasts. It is well compacted. Alteration is similar as in the underlying samples, with clays filling vesicles and replacing glass partially. Heu-type zeolites fill the remaining glass. Sample 06LM051 is a very fine claystone formed by pelagic fall-out, containing a high amount of quartz (74%) and minor brownish clays. Zeolites are rare and occur in voids which are mainly formed by dissolved microorganisms. Sample 06LM049 is a fine tuff containing a high amount of argillitized particles. The sample is probably reworked, because of the high amount of rounded particles. These particles are entirely replaced by brownish clays. Pumice and glass particles are rimmed by yellow clays, which also fill vesicles, while heu-type zeolites replace glass. Sample 06LM047 contains a high amount of quartz and calcite (21%). Sample 06LM044 is a tuff composed of small clasts, which are mainly

replaced by quartz. Other particles are replaced by brownish clays. Sample 06LM043 from the base of an overlying lapilli tuff layer, contains a low amount of quartz. It has a similar alteration as sample 06LM057. Glass is mainly palagonitized, smectite is filling vesicles, opal–CT is formed before large euhedral heu-type zeolites which replace opal–CT and which are filling voids of dissolved glass. Celadonite crystallises before brownish clays, but greenish chloritic clays can occur central in vesicles and are formed after smectite.

Section 2 of the upper unit

Sample 06LM036 was taken from a tuff layer underlaying a coarse lapilli tuff sequence. It is composed mainly of glass shards. Because alteration minerals are very fine-grained, it is difficult to distinguish between them. Glass shards are replaced mainly by heu-type zeolites, while fine quartz occurs between them. Sample 06LM035, from the base of a lapilli tuff sequence, is altered to a high amount of iron brown clays and reddish iron oxides. Clays rim particles, fill vesicles and replace part of the glass or all the glass of pumice clasts. Mordenite and opal–CT crystallise before heu-type zeolites. Heu–type zeolites replacing pumice are highly irregular and interlocking and replace opal–CT and mordenite. Mordenite forms very thin and long crystals in very loose aggregates, very different from the aggregates occurring in the lower unit of the Cayo Formation. Some particles contain very few vesicles and are replaced entirely by heu-type zeolites, but probably at these locations heu-type zeolites replace mordenite and opal–CT. In voids and vesicles, heu-type zeolites are more euhedral. Some particles were probably dissolved completely, resulting in the formation of euhedral and large heu-type zeolites crystallising in these empty voids. The quartz content is low in the sample (10%). Sample 06LM034 occurs higher in the same lapilli tuff sequence. It is altered to brownish clays and irregularly shaped heu-type zeolites. In voids, heu-type zeolites are larger and more euhedral. Radial opal–CT crystallises before


106

heu-type zeolites. No celadonite occurs, the quartz content is low (6%) and empty voids and cracks occur, which are not filled by late calcite as in the sequences occurring below. It is not always clear if zeolites fill vesicles or replace glass. Probably the glass was initially completely palagonitized, and heu-type zeolites fill the remaining voids. Samples 06LM032–033 are from a tuff bed occurring above the coarse lapilli tuff sequence. They are very fine-grained pelagic fallouts. Alteration is very fine-grained and composed of greenish to brownish clays, opal–CT and mainly quartz (68%). Sample 06LM031 is from a new coarse lapilli tuff sequence. It is altered to dark brown to yellow clays, which rim particles and fill vesicles and partly replace glass. Probably a high amount of mordenite formed in empty voids before heu-type zeolites, but all mordenite is replaced by heu-type zeolites. Heu-type zeolites preserve the radial shape of these mordenite aggregates. Some heu-type zeolite crystals are blocky, while others are more euhedral in shape. It is difficult to be sure if it was mordenite that is replaced by heu-type zeolites in these beds, because no remaining mordenite is detected by XRD, except for a low amount in sample 06LM035. Opal–CT seems to form smaller aggregates with thicker crystals, which have pyramidal terminations. Sample 06LM026 occurs in an overlying tuff layer and contains opal–CT and a high amount of quartz (65%). Higher in the section, the zeolite percentages drop drastically and opal-CT (nearly 80% in sample 06LM022) and quartz become the dominant alteration minerals (100% quartz in sample 06LM017). Sample 06LM024 is the uppermost sample containing heu-type zeolites of the Cayo Formation. The Guayaquil Formation has a similar mineralogy. The fine-grained beds are composed almost completely of quartz and minor opal-CT.

Rio Guaraguao

GPS point Sample Name X Y Height

06-001 593168 9768720 334

06-002 593951 9775242 130

06-003 06LM001 595877 9775746 65

06-004 06LM002 595877 9775746 65

06-004 06LM003 595148 9775894 75

06-005 06LM004 595214 9775846 67

06-006 06LM005 595446 9775490 65

06-006 06LM006 595446 9775490 65

06-006 06LM007 595446 9775490 65

06-006 06LM008 595446 9775490 65

06-006 06LM009 595446 9775490 65

06-006 06LM010 595446 9775490 65

06-007 06LM011 595639 9775618 62

06-008 06LM012 595661 9775652 68

06-008 06LM013: 595661 9775652 68

06-008 06LM014 595661 9775652 68

06-008 06LM015 595661 9775652 68

06-009 595808 9775606 55

06-010 06LM016 595678 9775322 72

06-011 595192 9775270 83

06-012 06LM017 595192 9775270 83

06-013 06LM018 595192 9775270 83

06-014 06LM019 595192 9775270 83

06-013 06LM020 593632 9768558 0

06-013 06LM021 593632 9768558 0

06-013 06LM022 593632 9768558 0

06-014 06LM023 593639 9768736 261

06-015 06LM024 593620 9768750 262

06-015 06LM025 593620 9768750 262

06-016 06LM026 593616 9768792 260

06-016 06LM027 593616 9768792 260

06-016 06LM028 593616 9768792 260

06-016 06LM029 593616 9768792 260

06-017 06LM30 593630 9768804 259

06-017 06LM031 593630 9768804 259

06-017 06LM032 593630 9768804 259

06-018 06LM033 593635 9768816 260

06-018 06LM034 593635 9768816 260

06-018 06LM035 593635 9768816 260

06-018 06LM036 593635 9768816 260

06-019 06LM064 593396 9769256 247

06-020 06LM040 593611 9768844 260

06-021 593614 9768856 0

06-022 593518 9768908 254

06-023 06LM041 593515 9768928 254

06-024 593507 9768940 254

06-025 593498 9768946 0

06-026 593481 9768990 243

06-027 593458 9769014 266

06-028 593447 9769032 257

06-029 593437 9769040 249

06-030 593413 9769068 245

06-031 593412 9769078 239

GPS point Sample Name X Y height

06-032 06LM060 593402 9769096 239

06-033 06LM061 593386 9769122 241

06-034 593371 9769142 249

06-035 593381 9769166 243

06-038 06LM042 593487 9768988 249

06-038 06LM043 593487 9768988 249

06-038 06LM044 593487 9768988 249

06-038 06LM045 593487 9768988 249

06-038 06LM046 593487 9768988 249

06-038 06LM047 593487 9768988 249

06-038 06LM048 593487 9768988 249

06-038 06LM049 593487 9768988 249

06-038 06LM050 593487 9768988 249

06-038 06LM051 593487 9768988 249

06-038 06LM052 593487 9768988 249

06-038 06LM053 593487 9768988 249

06-038 06LM054 593487 9768988 249

06-038 06LM055 593487 9768988 249

06-038 06LM056 593487 9768988 249

06-038 06LM057 593487 9768988 249

06-039 593470 9768996 249

06-040 593392 9769110 250

06-041 593378 9769124 250

06-042 06LM058 593377 9769184 247

06-042 06LM059 593377 9769184 247

06-043 593371 9769200 244

06-044 06LM062 593380 9769222 240

06-044 06LM063 593380 9769222 240

06-044 06LM064 593380 9769222 240

06-045 593340 9769286 233

06-046 593332 9769304 233

06-047 06LM065 593263 9769390 233

06-047 06LM070 593263 9769390 233

06-048 06LM071 593263 9769390 233

06-049 06LM066 593278 9769414 226

06-049 06LM067 593278 9769414 226

06-049 06LM068 593278 9769414 226

06-049 06LM069 593278 9769414 226

06-050 06LM072 593260 9769450 227

06-051 593235 9769472 224

06-052 593220 9769502 218

06-053 593211 9769538 222

06-054 06LM073 593235 9773908 111

06-055 06LM074 593214 9773918 115

06-055 06LM075 593214 9773918 115

06-055 06LM076 593214 9773918 115

06-055 06LM077 593214 9773918 115

06-056 06LM078 593170 9773940 115

06-057 06LM079 593054 9773834 114

06-057 06LM080 593054 9773834 114

06-058 593033 9773760 119

06-059 592998 9773660 112

06-060 06LM081 592986 9773630 120

06-060 06LM082 592986 9773630 120

06-060 06LM083 592986 9773630 120


06-061 06LM084 592986 9773630 120

06-061 06LM085 592986 9773630 120

06-062 06LM086 592973 9773588 127

06-063 06LM087 592976 9773572 126

06-064 06LM087bis 592995 9773488 125

06-065 06LM088 593058 9773388 131

06-066 593069 9773340 137

06-067 06LM089 593050 9773332 0

06-068 593032 9773326 126

06-069 06LM090 593003 9773336 126

06-069 06LM091 593003 9773336 126

06-070 06LM092 592972 9773342 128

06-071 06LM093 592887 9773342 129

06-071 06LM094 592887 9773342 129

06-075 595665 9775268 62

06-076 06LM095 595628 9775258 66

06-077 595600 9775260 71

06-078 06LM096 595502 9775294 65

06-078 06LM097 595502 9775294 65

06-078 06LM098 595502 9775294 65

06-079 595491 9775302 72

06-080 06LM098 595459 9775318 80

06-081 595396 9775410 74

06-082 595294 9775454 67

06-083 06LM099 595245 9775434 72

06-084 595236 9775406 72

06-085 06LM100 595212 9775394 70

06-085 06LM101 595212 9775394 70

06-086 06LM102 595173 9775240 65

06-087 595129 9775202 69

06-088 595081 9775142 72

06-090 06LM103 595035 9775012 69

06-092 594977 9774904 0

06-093 594972 9774802 56

06-094 06LM104 594975 9774776 54

06-095 06LM105 595024 9774654 78

06-095 06LM106 595024 9774654 78

06-096 595026 9774598 79

06-097 06LM107 594881 9774666 80

06-098 594815 9774680 76

06-099 594774 9774764 143

06-100 594661 9774670 134

06-101 594565 9774530 78

06-102 06LM108 594410 9774458 85

06-103 06LM109 594456 9774410 80

06-104 594515 9774370 81

06-105 06LM110 594552 9774356 91

06-106 06LM111 594577 9774282 101

06-107 594485 9774194 85

06-108 594450 9774240 108

06-109 06LM112 594360 9774240 91

06-110 06LM113 594305 9774162 93

06-111 06LM114 594213 9774130 82

06-112 594161 9774048 91

06-113 06LM115 594151 9773992 94


06-114 06LM116 594142 9773936 106

06-115 06LM118 594130 9773896 94

06-116 06LM117 594133 9773910 104

06-117 06LM119 594113 9773880 105

06-118 06LM120 594068 9773838 106

06-118 06LM121 594068 9773838 106

06-119 06LM122 594050 9773840 113

06-120 06LM123 594002 9773952 112

06-121 594022 9773996 117

06-122 593742 9774196 110

06-123 06LM178 593329 9774204 116

06-123 06LM179 593329 9774204 116

06-124 593279 9774136 120

06-125 06LM177 593281 9774040 118

06-126 06LM176 593322 9773990 118

06-127 06LM124 593293 9773896 120

06-128 06LM125 592805 9773334 128

06-128 06LM126 592805 9773334 128

06-128 06LM127 592805 9773334 128

06-128 06LM128 592805 9773334 128

06-129 06LM129 592786 9773316 132

06-129 06LM130 592786 9773316 132

06-129 06LM131 592786 9773316 132

06-129 06LM132 592786 9773316 132

06-129 06LM133 592786 9773316 132

06-129 06LM134 592786 9773316 132

06-129 06LM135 592786 9773316 132

06-130 06LM136 592739 9773318 126

06-130 06LM137 592739 9773318 126

06-131 06LM138 592715 9773274 129

06-131 06LM139 592715 9773274 129

06-133 06LM143 592603 9773366 127

06-133 06LM144 592603 9773366 127

06-134 06LM145 592461 9773240

06-134 06LM146 592461 9773240

06-134 06LM147 592461 9773240

06-135 06LM148 592454 9773228 133

06-136 06LM149 592286 9773214 135

06-137 592492 9773278 0

06-138 592750 9773006 131

06-139 592784 9772950 132

06-140 592785 9772892 132

06-141 592842 9772774 139

06-142 06LM150 592867 9772664 140

06-143 06LM151 592840 9772628 140

06-143 06LM152 592840 9772628 140

06-144 06LM153 592849 9772512 133

06-144 06LM154 592849 9772512 133

06-145 06LM155 592904 9772418 140

06-145 06LM156 592904 9772418 140

06-145 06LM157 592904 9772418 140

06-146 06LM158 592904 9772408 142

06-146 06LM159 592904 9772408 142

06-148 592915 9772372 142

06-149 592918 9772348 150


06-150 592885 9772322 146

06-151 06LM160 592751 9772344 147

06-152 592750 9772188 148

06-153 592719 9772116 157

06-154 592713 9772080 155

06-155 592777 9772014 156

06-156 592781 9771978 161

06-157 06LM161 592786 9771950 149

06-158 06LM162 592786 9771936 157

06-159 592780 9771906 155

06-160 06LM163 592683 9771702 157

06-161 592661 9771672 156

06-162 06LM164 592701 9771648 159

06-163 592916 9771654

06-164 06LM165 592943 9771608 166

06-165 592939 9771508 170

06-166 06LM166 592789 9771276 163

06-167 592712 9771252 168

06-168 592654 9771156 171

06-169 592661 9771082 169

06-170 06LM167 592652 9771044 172

06-171 06LM168 592634 9771012 175

06-172 592598 9770960 172

06-173 06LM169 592551 9770984 171

06-173 06LM170 592551 9770984 171

06-174 592532 9770800 177

06-175 592537 9770750 173

06-176 592577 9770674 170

06-177 06LM171 592597 9770574 179

06-177 06LM172 592597 9770574 179

06-177 06LM173 592597 9770574 179

06-178 06LM174 592566 9770568 190

06-179 592516 9770548 192

06-180 592453 9770550 188

06-181 592405 9770564 188

06-182 06LM175 592364 9770554 207

06-183 593214 9769550 230

06-184 592301 9770578 205

06-185 592288 9770584 205

06-186 06LM180 592268 9770472 174

06-186 06LM181 592268 9770472 174

06-186 06LM182 592268 9770472 174

06-187 06LM183 592325 9770418 190

06-188 06LM184 592567 9770342 188

06-188 06LM185 592567 9770342 188

06-188 06LM186 592567 9770342 188

06-189 592558 9770336 181

06-190 06LM187 592545 9770300 187

06-190 06LM188 592545 9770300 187

06-191 06LM189 592485 9770218 206

06-192 592530 9770182 200

06-193 592596 9770148 198

06-194 06LM190 592598 9770084 197

06-195 06LM191 592617 9769996 189

06-195 06LM192 592617 9769996 189


06-196 06LM193 592684 9769950 197

06-197 06LM194 592708 9769906 196

06-197 06LM195 592708 9769906 196

06-198 06LM196 592700 9769874 224

06-198 06LM197 592700 9769874 224

06-199 592755 9769786 213

06-200 592797 9769734 213

06-201 592814 9769726 209

06-202 592856 9769702 211

06-203 06LM198 592878 9769686 224

06-205 06LM199 592964 9769642 214

06-205 06LM200 592964 9769642 214


09-003 593300 9773804 148

09-004 589317 9794519 46

09-005 582726 9785605 72

09-006 595000 9774884 98

09-007 09LM001 594981 9774979 69

09-008 594979 9774801 58

09-009 09LM002 594980 9774830 70

09-009 09LM003 594980 9774830 70

09-009 09LM004 594980 9774830 70

09-010 09LM005 594972 9774822 71

09-010 09LM006 594972 9774822 71

09-011 09LM007 594981 9774814 97

09-012 09LM008 594979 9774782 78

09-012 09LM009 594979 9774782 78

09-012 09LM010 594979 9774782 78

09-012 09LM011 594979 9774782 78

09-013 594990 9774727 72

09-014 595022 9774667 84

09-015 09LM012 595038 9774650 87

09-016 09LM013 594977 9774615 97

09-017 09LM014 594939 9774634 92

09-017 09LM015 594939 9774634 92

09-018 09LM016 594891 9774672 101

09-019 09LM017 594856 9774682 81

09-020 09LM018 594846 9774682 74

09-021 09LM019 594836 9774680 69

09-022 594819 9774695 85

09-023 594807 9774719 98

09-024 09LM020 594689 9774703 149

09-025 09LM021 594657 9774670 132

09-026 09LM022 594650 9774661 106

09-027 09LM023 594643 9774651 103

09-028 594609 9774598 114

09-029 09LM024 594549 9774535 109

09-030 09LM025 594540 9774530 104

09-031 09LM026 594521 9774521 97

09-032 09LM027 594524 9774515 85

09-033 09LM028 594423 9774492 101

09-034 594413 9774474 88

09-035 09LM029 594422 9774450 89

09-036 09LM030 594398 9774451 98

09-037 09LM031 594409 9774447 100


09-038 594451 9774419 101

09-039 594476 9774393 112

09-040 09LM032 594564 9774289 107

09-041 594544 9774197 104

09-042 594501 9774190 103

09-043 09LM033 594441 9774232 102

09-044 594441 9774232 102

09-045 594402 9774253 86

09-046 594393 9774255 84

09-047 09LM034 594288 9774174 90

09-048 594243 9774143 91

09-049 594185 9774113 86

09-050 09LM035 594149 9774053 97

09-051 594166 9774017 97

09-052 09LM036 594153 9774015 97

09-053 09LM037 594151 9773992 103

09-054 09LM038 594139 9773970 104

09-055 09LM039 594138 9773936 104

09-056 09LM040 594140 9773931 100

09-057 09LM041 594142 9773919 94

09-057 09LM042 594142 9773919 94

09-058 594135 9773907 110

09-059 594127 9773893 113

09-060 09LM043 594054 9773835 115

09-061 594006 9773905 106

09-062 594007 9773932 117

09-063 592987 9773627 118

09-064 09LM044 592977 9773600 115

09-065 09LM045 592969 9773581 121

09-066 592976 9773538 119

09-067 09LM046 592967 9773542 118

09-067 09LM047 592967 9773542 118

09-067 09LM048 592967 9773542 118

09-067 09LM049 592967 9773542 118

09-068 09LM050 592968 9773526 124

09-069 592997 9773493 121

09-070 593013 9773456 123

09-071 09LM051 593071 9773374 127

09-071 09LM052 593071 9773374 127

09-071 09LM053 593071 9773374 127

09-072 593070 9773338 133

09-073 09LM054 593068 9773327 117

09-074 09LM055 593046 9773331 115

09-074 09LM056 593046 9773331 115

09-074 09LM057 593046 9773331 115

09-074 09LM058c 593046 9773331 115

09-074 09LM058f 593046 9773331 115

09-075 09LM059 593033 9773331 118

09-075 09LM060 593033 9773331 118

09-076 09LM061 593024 9773328 121

09-077 09LM062 593014 9773332 121

09-078 09LM063 593003 9773332 121

09-078 09LM064 593003 9773332 121

09-079 09LM065 592990 9773336 120

09-079 09LM066 592990 9773336 120


09-079 09LM067 592990 9773336 120

09-080 09LM068 592959 9773344 122

09-080 09LM069 592959 9773344 122

09-081 592931 9773345 124

09-082 09LM072 597401 9775988 87

09-083 09LM073 597318 9775916 79

09-083 09LM074 597318 9775916 79

09-084 09LM075 597273 9775903 95

09-084 09LM076 597273 9775903 95

09-085 09LM077 597221 9775954 66

09-085 597221 9775954 66

09-086 597109 9775969 86

09-087 09LM070 597052 9775914 78

09-087 09LM071 597052 9775914 78

09-088 596837 9776002 82

09-089 596760 9776004 70

09-090 596751 9776081 67

09-091 596584 9776094 81

09-092 596536 9776062 76

09-093 596497 9776077 72

09-094 09LM078 596447 9776047 61

09-095 09LM079 596373 9775918 74

09-095 09LM080 596373 9775918 74

09-096 596299 9775938 89

09-097 596281 9776008 75

09-098 596174 9776041 72

09-099 595971 9776057 67

09-100 09LM081 595892 9775961 65

09-100 09LM082 595892 9775961 65

09-100 09LM083 595892 9775961 65

09-101 595870 9775668 83

09-102 595627 9775263 72

09-103 595550 9775268 72

09-104 09LM084 595541 9775271 67

09-105 09LM085 595487 9775301 71

09-106 595467 9775306 65

09-107 595368 9775417 63

09-108 595260 9775431 66

09-109 09LM086 595225 9775327 72

09-110 09LM087 595169 9775249 62

09-111 09LM088 595049 9775064 75

09-111 09LM089coarse 595049 9775064 75

Guayaquil area


06-223 06LM203 619348 9773486 14

06-224 06LM204 619951 9773874 118

06-225 06LM205 619997 9774002 120

06-226 06LM206 620073 9773870 113

06-226 06LM207 620073 9773870 113

06-227 06LM208 620081 9773856 105

06-227 06LM209 620081 9773856 105

06-228 06LM210 620310 9773618 59

06-228 06LM211 620310 9773618 59

06-229 06LM212 622032 9773802 20

06-231 06LM213 625372 9772654 21

06-231 06LM214 625372 9772654 21

06-231 06LM215 625372 9772654 21

06-231 06LM216 625372 9772654 21

06-233 626868 9776810 22

06-236 06LM217 627084 9776342 29

06-236 06LM218 627084 9776342 29

06-236 06LM219 627084 9776342 29

06-241 06LM220 621655 9771476 26

06-241 06LM221 621655 9771476 26

06-242 06LM222 620847 9770948 47

06-242 06LM223 620847 9770948 47

06-242 06LM224 620847 9770948 47

06-243 06LM225 620871 9770894 40

06-243 06LM226 620871 9770894 40

06-244 06LM227 619268 9770474 19

06-244 06LM228 619268 9770474 19

06-246 06LM229 620360 9768700 14

06-246 06LM230 620360 9768700 14

06-247 06LM231 620357 9768688 15

06-247 06LM232 620357 9768688 15

06-248 06LM233 620366 9768680 15

06-249 06LM234 620355 9768650 13

06-249 06LM235 620355 9768650 13

06-249 06LM236 620355 9768650 13

06-250 06LM237 620351 9768622 15

06-251 06LM238 620335 9768610 16

06-252 06LM239 620319 9768584 24

06-265 06LM243 619044 9770520 29

06-266 06LM242 619120 9770514 20

06-267 06LM241bis 619155 9770514 31

06-268 622770 9771422 16

06-269 06LM244 622864 9771136 17

06-269 06LM245 622864 9771136 17

06-270 06LM246 622837 9771190 11

06-271 06LM247 622821 9771236 17

06-272 06LM248 622805 9771298 12

06-272 06LM249 622805 9771298 12

06-273 622795 9771324 15

06-274 06LM250 622762 9771384 15

06-276 06LM251 622997 9770586 12

GPS point Sample Name X Y Hight

06-277 06LM252 622992 9770694 14

06-285 06LM253 621531 9770304 50

06-286 06LM254 621420 9770288 34

06-287 06LM255 621435 9770002 16

06-287 06LM256 621435 9770002 16

06-287 06LM257 621435 9770002 16

06-288 06LM258 621465 9770012 17

06-290 06LM259 621457 9769968 24

06-291 06LM260 621473 9769914 27

06-291 06LM261 621473 9769914 27

06-292 06LM262 621481 9770014 20

06-294 619974 9771868 23

06-296 06LM263 620070 9772240 17

06-297 06LM264 620093 9772126 18

06-298 06LM265 620200 9768700 17

06-298 06LM266 620200 9768700 17

06-300 06LM267 619874 9767614 24

06-300 06LM268 619874 9767614 24

06-300 06LM269 619874 9767614 24

06-300 06LM270 619874 9767614 24

06-303 06LM271 617007 9774144 46

06-304 06LM272 617255 9773884 25

06-305 06LM273 617316 9774382 39

06-305 06LM274 617316 9774382 39

06-305 06LM275 617316 9774382 39

06-306 06LM276 615109 9772376 52

06-310 614988 9770394 80

06-311 06LM277 614945 9770428 90

06-311 06LM278 614945 9770428 90

06-311 06LM279 614945 9770428 90

06-312 06LM280 614944 9770472 99

06-312 06LM281 614944 9770472 99

06-313 06LM282 614959 9770176 60

06-315 06LM283 614888 9769980 55

06-320 06LM284 614489 9766244 157

06-321 06LM285 614309 9766188 115

06-322 613859 9769116 81

06-323 613851 9769328 77

06-324 613815 9769124 76

06-325 613855 9769012 79

06-326 613702 9768878 76

06-327 613824 9769184 75

06-328 613879 9769034 75

06-329 613805 9760914 74

06-330 613675 9768804 73

06-331 613674 9768676 74

06-332 613674 9768590 66

06-334 613654 9768350 75

06-335 613668 9768212 74

06-336 613719 9768116 76

06-338 06LM288 613733 9768052 78


06-339 06LM286 613682 9768010 75

06-340 06LM287 613639 9767986 75

06-341 613568 9767956 76

06-343 06LM288bis 613519 9767948 81

06-344 06LM289 613499 9767940 79

06-345 06LM290 613460 9767926 72

06-345 06LM291 613460 9767926 72

06-346 06LM287bis 613533 9767966 70

06-350 613583 9767010 68

06-351 613598 9766988 70

06-352 613612 9766960 70

06-353 06LM292 613630 9766914 66

06-353 06LM293 613630 9766914 66

06-353 06LM294 613630 9766914 66

06-353 06LM295 613630 9766914 66

06-354 613670 9766836 64

06-355 06LM296 613682 9766810 65

06-356 613697 9766790 69

06-357 06LM297 613713 9766754 72

06-357 06LM298 613713 9766754 72

06-358 06LM299 613733 9766714 69

06-359 613749 9766684 75

06-360 06LM300 613755 976678 78

06-361 613773 976636 76

06-362 614224 9766104 65

06-365 614105 9770286 36

06-366 615205 9771650 78

06-369 06LM301 615081 9771480 75

06-370 614966 9771328 81

06-371 614961 9771018 82

06-372 615050 9770796 81

06-373 615015 9770558 79

06-374 06LM302 614886 9770454 80

06-375 614947 9770502 0

06-376 614604 9770394 78

06-378 06LM303 613399 9765504 48

06-379 613429 9765028 71

06-380 613282 9764716 71

06-381 612977 9764436 73

06-382 612740 9764334 78

06-383 612537 9764422 75

06-384 612209 9764402 73

06-385 612015 9764452 72

06-386 613489 9765342 73

06-387 613484 9765972 59

06-388 06LM304 616513 9768572 41

06-389 06LM305 616720 9768526 51

06-389 06LM306 616720 9768526 51

06-390 617232 9768398 46

06-391 617232 9768362 44

06-392 617223 9768326 45


06-393 617242 9768296 43

06-394 617242 9768222 41

06-395 06LM307 617248 9768184 44

06-396 617249 9768166 48

06-397 06LM308 617264 9766306 11

06-397 06LM309 617264 9766306 11

06-397 06LM310 617264 9766306 11

06-398 06LM311 617341 9766236 37

06-399 06LM312 617078 9765766 36

06-400 617201 9764694 45

06-401 06LM313 617217 9764660 45

06-401 06LM314 617217 9764660 45

06-401 06LM315 617217 9764660 45

06-402 06LM316 617222 9764630 50

06-403 06LM317 617236 9764604 46

06-404 06LM318 617241 9764580 48

06-406 617466 9763988 45

06-407 06LM319 617467 9763974 45

06-408 617470 9763962 45

06-409 06LM320 617476 9763952 49

06-410 617475 9763943 48

06-411 617478 9763926 50

06-412 617479 9763908 50

06-413 617276 9764572 45

06-414 06LM321 617286 9764546 49

06-415 617295 9764522 50

06-416 06LM322 617304 9764500 0

06-417 617304 9764500 0

06-418 06LM323 617304 9764500 0

06-418 06LM324 617304 9764500 0

06-419 06LM325 617304 9764500 0

06-420 617304 9764500 0

06-421 617332 9764408 49

06-422 617453 9763846 56

06-423 617452 9763824 54

06-424 617462 9763774 59

06-425 617466 9763760 58

06-426 617466 9763750 56

06-427 617463 9763754 55

06-428 617469 9763706 56

06-429 617482 9763606 0

06-430 06LM327 617301 9764507 53

Rio de la Derecha


09-124 09LM090 578163 9781440 122

09-125 09LM091 578161 9781418 141

09-126 09LM092 578162 9781406 137

09-126 09LM093 578162 9781406 137

09-127 09LM094 578164 9781404 139

09-128 09LM095 578157 9781395 136

09-129 09LM096 578155 9781392 138

09-130 09LM097 578151 9781384 138

09-131 09LM098 578150 9781381 141

09-131 09LM099 578150 9781381 141

Rio Zamoreño


140 09LM104 574413 9783733 70

140 09LM105 574413 9783733 70

142 09LM100 574495 9784020 69

151 09LM101 574399 9783892 176

151 09LM102 574399 9783892 176

151 09LM103 574399 9783892 176

152 09LM106 574397 9783693 194

153 09LM107 574394 9783683 195

154 09LM108 574377 9783661 200

155 09LM109 574378 9783652 189

156 09LM110 574374 9783651 199

156 09LM111 574374 9783651 199

157 09LM112 574361 9783648 203

159 09LM113 574349 9783631 225

160 09LM114 574317 9783623 212

161 09LM115 574300 9783615 202

162 09LM116 574295 9783616 201

166 09LM117 574219 9783502 187

167 09LM118 574256 9783363 201

168 09LM119 574271 9783316 192

Manabí area


583 06LM428bis 533074 9831388 97 Agua Blanca

585 06LM430 534871 9832864 133 Agua Blanca


585 06LM431 534871 9832864 133 Agua Blanca


578 06LM427 521906 9828938 22 Puerto Lopez

578 06LM428 521906 9828938 22 Puerto Lopez

542 06LM406 527996 9824070 188 Rio Mocora

543 06LM407 527736 9824330 176 Rio Mocora

558 06LM411 531814 9822416 408 Rio Mocora

569 06LM421 530250 9822864 227 Rio Mocora

572 06LM424 529553 9823220 197 Rio Mocora

572 06LM425 529553 9823220 197 Rio Mocora

450 06LM337 550049 9816632 385 Rio Ayampe

454 06LM341 545456 9815410 277 Rio Ayampe

453 06LM343 545792 9815256 279 Rio Ayampe

461 06LM345 546471 9815330 261 Rio Ayampe

472 06LM347 547941 9815580 291 Rio Ayampe

477 06LM350 548151 9815906 309 Rio Ayampe

480 06LM351 549050 9816440 314 Rio Ayampe

504 06LM378 540789 9817082 171 Rio Ayampe

527 06LM396 527719 9815264 49 Rio Ayampe

527 06LM397 527719 9815264 49 Rio Ayampe

534 06LM402 525737 9814742 28 Rio Ayampe

536 06LM404 525429 9814938 35 Rio Ayampe

Documents

Appendices – Table of contents - KU Leuven · Appendices – Table of contents Appendix 1 - Stratigraphy of the Late Cretaceous deposits: previous work ... named Volcanismo tardío