A sketch of the geology of the whitehaven district

GEOLOGY OF THE WHITEHAVEN DISTRICT. 37

and Chatteris are on the line of presumed strike of the upperrenggeri beds.

As Mr. Pringle implies, * the recent observation at a boringat Long Sutton (16 miles north of March) of Upper Oxford Clayand Lower Ampthill Clay directly underlying the Boulder Clayfurther supports the idea that the western boundary of theKimmeridge Clay is to be found east of the " March Island."As Long Sutton is north of the fault by which the beds are displaced westwards the above occurrence is regarded as especiallysignificant.

In conclusion, the writer wishes to record his indebtednessto the managers of the various brickfields around Peterboroughfor facilities (readily granted) to examine the sections; alsoto Professor P. G. H. Boswell for verifying the determination·of the detrital minerals from the Kellaways Beds of Werrington.

A SKETCH OF THE GEOLOGY OF THEWHITEHAVEN DISTRICT.

\By BERNARD SMITH, M.A., Sc.D.; E. E. L. DIXON, A.R.C.Se., B.Se.; T. EASTWOOD,A.R.C.Se. ; C. EDMONDS; and S. E. HOLLINGWORTH, B.A., B.Se.

THE Whitehaven district, situated on the western flankof the main Lake District massif, offers problems in geology

quite as interesting as, if differing in type from, those of themuch better known and more frequented Lake District proper.

This western plain (as distinct from the Fells) is diversifiedand exhibits strong variations in relief. It is trenched byseveral important valleys and its coast scenery in places attainsgrandeur. Near Dean Moor and Arlecdon it rises to about 700feet above sea-level, but the general average is nearer 400 feet.St. Bees Headland reaches its highest point in Hannah Moor,west of Rottington, at 466 feet O.D.

The most remarkable physiographical feature, perhaps,is the St. Bees-Whitehaven gap, traversed by the FurnessRailway, which isolates St. Bees Headland, known as PrestonIsle, from the rest of the plain, as a low-level through valleywhich, if drowned, might be compared with the Solent or theMenai Straits.

From Cockermouth to Ennerdale the western margin of theFell country occurs as a nearly north-and-south line; south ofEnnerdale, however, it swings westward for several miles toDent, and then southward to the neighbourhood of Egremont.Thereafter it runs eastward and south-south-eastward past Gosforth.

To the north the combined Derwent and Cocker enter thesea at Workington, whilst the Ehen, issuing from Ennerdale

• Summary of Progress for 1921, p. III, Aleln. Geol, Sun'., 1922.

GEOLOGY OF THE WHITEHAVEN DISTRICT.

1J Brockram

Skiddaw Slates

Ennerdale Granophyre; dykes and sills.

ORDOVICIANt, and

? CAMBRIAN

CARBONIFEROUS

IGNEOUS

Water, rounds the protruding shoulder of Dent and, turningdue south past Egremont, enters the sea at Sellafield, whereit mingles its waters upon the beach with those of the Calder.The Keekle Beck, an important tributary of the Ehen, joins itnear Cleator. The Whitehaven-St. Bees gap is drained northward and southward by two small streams, obvious misfits,whose headwaters occur upon the sides of the valley, bothknown as the Pow Beck.

A complete and connected account of the geology of thisdistrict has yet to be written, although much work has beendone both by local and other workers and by the officers ofthe Geological Survey.

A list of published works will be given in the forthcomingMemoir on Sheet 28, Whitehaven.

Apart from Russell, Aveline, Sir A. Strahan, Ward andothers, whose official work is incorporated upon the six-inch andone-inch maps of the Survey, probably most work has beendone by Mr. J. D. Kendall, who was long resident in the areaand whose observations have been put out from time to timein a number of important publications, some of which are referredto below.

Summary accounts have appeared recently describing theprogress of the present re-survey, whilst special descriptionshave been written* of the Ennerdale Granophyre, the Hzernatite Iron Ores and the Brockram, the Carboniferous LimestoneSeries, and Glacial Phenomena near Ennerdale.

The following formations are represented:-RECENT and Peat, Alluvium and GlacialPLEISTOCENE Deposits.

{

Kirklinton SandstoneTRIAS St. Bees Sandstone

(St. Bees ShalesPERMIAN JlMagnesian Limestone

BrockramGreat Unconformity.

\

Whitehaven Sandstone Series.Unconformity

Productive Coal MeasuresMillstone Grit

? Unconformity.Carboniferous Limestone Series.

Great Unconformity.Borrowdale Volcanic Series

The most important stratigraphical breaks occur (i) at thebase of the New Red Rocks which rest unconformably upon all

• Bv R. H Rastall , Bernard Smith, Charles Edmonds and E. E. L. Dixon.

O. nt

".: .: .: .. ..:. ..

L/t';C'lJ."

~~~ I~ ,- ~

INOI!:)(

I~ 8 1:e l I AHOIT ONE

.......OHE. 'AH ", "IITOHE8AOCM" ....COAL ... e ~Al.

",IUJTDNC C... ,

C"'ABOHlr[AOU' u .,r;ITO'"

IIOIIAC)WO.A",r VO"'CAH 'CAOC.' eTCSI( IOO...W'",ATEI

ENN l.RQALE GRA",OPHYR (

H,6,f ... ...TlTI ...0-1( '" 0 ... 'I l l

'A U .. , . AAI ' MOWN B"TH10l. . 1,. ...CI( LIN.'

Mil.. &I ,

" L _

ot%1oSC'l0<o."

.-l=::t%1

~::;t%1

~t%1Z

tj

~~

~

Vol\0

FIG. 5.-MAp OF THE WHITEHAVEN DISTRICT, CUMBERLAND , SHOWING THE SOLID G E OLOGY.


the lower members; (ii) at the base of the Carboniferous Limestone Series. Breaks of less magnitude occur below the Millstone Grit and below the Whitehaven Sandstone Series.

SKIDDAW SLATES.

From Cockermouth to Egremont the Skiddaw Slates formthe Fell country, and apparently underlie the younger formations farther to the west. They consist chiefly of alternations ofblue-grey or grey clay-slates and fine-grained silts or sandstones,and striped quartzites with rare and thin bands of fine conglomerate, nowhere very strongly cleaved. Grits are of morecommon occurrence in the Lamplugh district than that of Dent,where obscure graptolites have been discovered in uncleaved beds.

Outside the area affected by the intrusion of the granophyrethe slates are strongly folded in concertina manner in places,and over large areas both their age and structure remainobscure. Graptolites, pointing to a late Arenig (or Llanvirn Pjage have been found, during the resurvey, near Wath Mill,Cleator Moor; and around Loweswater, where a partial sequencehas been determined, the D extensus Zone is well developed(' Summary of Progress for 1924 '). Mr. J F. N. Green claimsthat the soft Upper Skiddaw Slates occur on Latterbarrowand pass upwards conformably into the Latterbarrow Sandstoneand overlying volcanic tuffs and agglomerates.*

Over most of the area farther north, remapped to date, thebeds show a north-westerly dip of from 30° to 60°, which is probably illusory, for in a few clear sections it is seen to be theinclination of the limbs of isoclinal folds, which have a gentlesouth-westerly pitch.

As the granophyre is approached south of Ennerdale, thefolding becomes less and less intense and unfolded beds with ageneral dip to the south-south-west margin the granophyreitself over a belt It miles in width.

Striped hornfels and spotted slates, resulting from theintrusion of the Ennerdale Granophyre, are widely but irregularly developed north of Ennerdale. South of Ennerdale, however, the above-mentioned belt has been hardened, either whollyor in part. When the whole width is affected there is somesuggestion that it is due to granophyre underlying the area.

The metamorphism is being studied microscopically fromnew material and from that collected by Dr. Rastall.

A number of dykes with general north-west trend traversethe slates in the Dent and Flat Fell district; they vary fromlight felspathic to dark basic types.

BORROWDALE VOLCANIC ROCKS.

These rocks appear on Wilton Fell and occupy the southeastern part of our district. The latest interpretation, by

* ]. F. N. GREEN, 1917, The Age of the Chief Intrusions of the Lake District, Proc. Gecl,Assoc.~ vel, xxviii, pp. 8-10, and PI. 1.


Mr. J. F. N. Green,* who includes the Latterbarrow Sandstonewith the Volcanic Series, differs from that of Ward and Sir A.Strahan. This ground has yet to be resurveyed. Up to thepresent our chief acquaintance with the Volcanic Rocks is inborings put down through the New Red and CarboniferousLimestone Series south of Egremont. Usually they appear asgreenish tuffs and ashes with lavas of andesitic types.

ENNERDALE GRANOPHYRE.

This great intrusion (or series of.intrusions) of laccolitic formhas been described petrographically by Dr. R. H. Rastall. tThe part which is now being resurveyed is chiefly located alongthe junction between the Skiddaw Slates and the BorrowdaleVolcanics. In Ennerdale contacts with both series may bestudied and the effects of the metamorphism observed.

This great series of intrusions is far from uniform. Thebulk of it is highly acid, but in many parts there are basic modifications such as occur on Bowness Knott, north of the lake,and another has been noted recently as a mile-long strip alongthe crags at 1000 feet, on the south side of the lake, commencing1 mile south of Anglers Crag. In places the margin is granitic,coarsely graphic, felsitic or porphyritic.

In the average rock the granophyric structure is carried toa very high degree of perfection. The microscopic appearanceis that of a fine-textured granite, usually of a bright pinkcolour, but occasionally grey with only a slight tinge of red.The rock is rarely porphyritic to the unaided eye and dark-coloured basic patches are also scarce.]

Dykes on the whole are rare. In addition to aplitic typeson Stair Knott,§ a beautiful acid dyke] has been recently tracedfor! mile, running a few degrees north of east, up the Scawtowards Starling Dodd. This has well-developed and highlycontorted coarsely spherulitic banding at the margins, and isapparently similar to the acid dyke inBurtness Coombe, Buttermere.~

The age of the granophyre is considered** to be previous tothe main folding or cleavage induced by the Caledonian earthmovements, and the above-mentioned observations by Mr.Hollingworth on the absence of folding in the metamorphicbelt south of Ennerdale Water bear this out.

CARBONIFEROUS LIMESTONE SERIES.

The outcrop of the rocks of this series forms a comparativelynarrow belt flanking the hills from Cockermouth to Egremont,

• op cit., p. 102, PI. I.t R. H. RASTALL, 1900, The Buttermere and Ennerdale Granophyre, Quart. [ourn; Geol •

.Soe., vol. lxii, pp. 253-74.tOp. cit., p, 258.§ or. cit., p. 261.

JI S .. E. HOLLINGWORTH, Summary of Progress for 1923 (l\1<m. Geol, Sun'.), p, 70.~ R. H. R.\ST<LL, op. cit., p. 269.•• R. H. R'5TAU., op, cit., p, 269, and J. F. N. GREEN, op. cii., p, rs.

CORRELATION OF THE CARBONIFEROUS LIMESTONE SERIES OF WHITEHAVEN.Zone . Sub-zone . Whiteh aven Area. Furness Area . Alston Moor Area.

Upper sub-zone Sne bro Gill Beds Shales, sandsto nes andD y Hensingharn Gr it limestones

Fi rst Limestone Great Limest oneMiddl e sub-zone Seco nd Limestone Yoredale Beds

D2 Third of Four Fathom Limestone" St ank, Gleaston, &c.F ourth to Giruanella Band in

Dibunophyllum to Girvanell~ Band at (top unknown) Robinson 's ( = Oxford)Zone ba se of " Ro ugh Lime- Limestone

s tone ..Lower s ub-zone Fo u rth Limest one Limestone of Askham, Melmerby Scar

D, r White Beds ") Lindale to Little LimestoneF ifth Limest one Urswick, AldinghamSixth "

to Con ishead ,(S pirilerina lam inosa) Seventh Limestone Limestones of ? = Scremerston andNe matophyitum minus iS piriterina d. lamin osa Longlands,Edge Hall, P lashetts Coals

sub-zone 52 at t op ) &c.Basement Beds

Productus Cyr tina carbonariacorrugato-hemisphericus sub-zone S2

ZoneGasteropod Beds 5, Gaste ro pod limestones

of Lindal Cote, GreatUrswick , &c.

Michelinia C. Limestones With occa -Zone sional sha les, of

Elli scales, Dalton , &c.A thyris glabristria • Semi nula gregaria Limestones with sh ales

Zone sub-zone C, and conglomerates

-• The correlation o! the S, mitJlIJa K"Karia sub-zone wit h C, is that suagested by Pro! Gar wood.


south of which they are overlapped by the New Red Series.Their average dip is westward beneath the higher membersof the Carboniferous System that extend to the coast-line fromMaryport to some distance south of Whitehaven. Inliers occurnear Distington and Hensingham and an outlier is faulted in atWilton Fell.

By Mr. J. D. Kendall* the series was divided into seven groups.of limestone separated by shales and sandstones. Upon theold One-inch Survey Map only one of these intervening beds-the Orebank Sandstone-is picked out.

More recently the series has been described by Mr. C. Edmonds] who, on palseontological grounds, accepts Mr. Kendall'smain grouping, but makes a different correlation with otherareas.

In borings made near Maryport] a few years ago, and atthe outcrop in that neighbourhood, a thick series of beds belonging to the Carboniferous Limestone Series overlies the FirstLimestone of Kendall which hitherto has been regarded as thetop of that Series. Hence it is not surprising that beds in theWhitehaven District also, which have hitherto been consideredto be Millstone Grit, have been found by Messrs. Eastwood andPringle to belong to the Carboniferous Limestone Series. Thesehave been named Snebro Gill Beds with basal Hensingham Grit,from the localities where they are best exposed near Whitehaven.They account for practically the whole of the " Millstone Grit"of the old One-inch Map (p. 39).

The following, therefore, is the sequence of the CarboniferousLimestone Series in the Whitehaven area§ :-

Sne bro Gill Beds ..Hensingham Grit ..First, Top or Langhorn LimestoneFirst Shale and Little WhirlstoneSecond LimestoneOrebank SandstoneThird LimestoneThird ShaleFourth or Clints LimestoneFourth ShaleFifth LimestoneFifth Shale (sandstone and shale)Sixth Limestone . . . . . .Sixth Shale (limestones, shales and mudstones)Seventh or Bottom LimestoneBasement Beds,

(Unconformable upon eroded Skiddaw Slate or

S.W. N.E.

40 6012 1414 24

40 70

12 I.')6 8

256 3u14 2450 70

14 24

54 70

10 ao60 [170] 160

3 6

Volcanic Rocks.v

• J. D. KENDALL, 1893. Iron Ores of Great Britain and Ireland, London, pp. 59-64.t C. EDMONDS, 1922, The Carboniferous Limestone Series of West Cumberland, Geol...Ma,g.,

PP. 74-83 and II7-131.t B. SMITH, 1921. Borings for Coal near Maryport, in Summary of Progress for 1920 (Mem.

Geol, Surv.), Appendix III, pp. 85-91.§ Thicknesses in feet as determined by Mr. Edmonds.

44 GEOLOGY OF THE WHITEHAVEN DISTRICT.

DETAILS OF FOURTH LIMESTONE.

Black Cherty Beds: limestones with chert nodules.Shale: mottled concretionary mudstone.Junceum Limestones: with cherts.Nodular and porcellanous limestone (algal ?)Saccamina Shale and Limestone.Micaceous Sandstone.Potholes Limestone.Shale and mudstone.Spotted Limestone.Thin mudstone (absent at Frizington and to north).Rough Limestones (dark grey).Shale, mudstone and calcite-mudstone.White Limestones, with three or four mottled shales and mudstones, a

persistent even-bedded limestone-breccia at the base.

It should be pointed out that in the Bigrigg-Beckermetdistrict it is the practice of local mining engineers to considerthe Third and Fourth Limestones as one unit-the Third-andthus restrict the number of limestones to six instead of seven.Again, if expedient, the Fourth Limestone could be split up,both lithologically and palseontologically, into more than onebed, thus increasing the number of the limestones. By theintercalation of shales, etc., this actually occurs in nature in thelateral passage of the limestones from West to East Cumberland.

The Geological Magazine paper cited above also details thefaunal features of the various limestones, and on this basis correlates the West Cumberland development of the CarboniferousLimestone Series, in part bed for bed, with those of Alston andthe N.W. Province generally. The correlation is embodied inthe table on page 42. Attention may be drawn to the correlation of the First with the Great Limestone, the Second with theFour Fathom, the recognition of the Girvanella Bed at the baseof D2 , and the fixing of the base of the whole series at theN ematophyllum minus sub-zone.

The recognition of the previous "Millstone Grit" as belonging to the Limestone Series introduces new problems into WestCumberland geology. Overlying the First Limestone is theHensingham Grit, varying in type from point to point, butoften felspathic and micaceous. At Overend, Hensingham,it is about 50 feet in thickness and contains numerouscasts of plants, the commonest of which is Lepidodendron. As developed in Snebro Gill, Hensingham,* thesucceeding beds consist of 100 feet or more of dark shalesand thin and lenticular beds of limestone, and sandstones whichare in places calcareous. A sponge-spicule bed on the otherhand is a cherty type. The limestones vary from dark earthyand sandy to pale shaly and crinoidal, and yield the fauna listedbelow. On the average the Grit and Snebro Gill Beds together

• T. Ea.STWOOD, 1923, in Summary of Progress for 1922 (Mem. GtJOl. Sun}.), p. 64.

PROC. GEOL. Assoc., VOL. XXXVI. PLATE 6.

Gcol; S urv. Photo.

CONTEM P ORANE OUS POTHOLES IN SUR FA CE OF "POTHOLES B E D. " C l i n t ' s Q uar r y , Bigrigg,

[T o [ace p. 45.


are about 200 feet thick in the Whitehaven district. They areimmensely thicker near Maryport.

The Snebro Gill Beds will be more fully described in a separatepublication in the near future. For the present it may sufficethat the following fossils, amongst others, have been found andidentified by the Palseontological Department of H.M. GeologicalSurvey.

FOSSILS FROM THE SNEBRO GILL BEDS.Zaphrentis sp. nov. [near Z. MeekeUa d. leei 1. Thomas

disjuneta. R. Carr.] Sanguinolites striaio-lamellosus (deChonetes laguessiana de Kon. Kon.)Productus d. concinnus J. Sow. Ewphemus urei (F1em.)

longispinus J. Sow. 'Pleuronautilus d. nodoso-carinatus.. d. scabriculus (Mart.) F. Roemer' [Foord and Crick

Schellunenetla crenistria (Phill.) interpret.] = Nautilus nodi/crusSpiri/er bisulcatus J. de C. Sow. Armstrong

Snebro Gill Beds have been recognised again above the Gritat the outcrop near Bigrigg and in the Barfs inlier nearDistington.

Amongst other points of lithological interest are the evidencesthat the main beds of limestone were deposited in shallow waters.Contemporaneous pot-holes (PI. 6) occur at several horizonsin the Fourth Limestone and testify to repeated intervals duringwhich subsidence and deposition of limestone were interruptedby elevation above sea-level and subaerial erosion.* Sanddykes, or joints filled with sand almost contemporaneouslywith the deposition of the beds, are found in the First Limestone] and bear comparison with the "riders" in the Productive Measures noticed by Prof. Gilligan in the Whitehaven Colliery.] The presence of contemporaneous breccias,algal beds, calcite-mudstones and cross-bedded sands in thelimestones at different horizons bears witness to shallowwater or even lagoonal conditions of deposition.

The basement beds of the Carboniferous Limestone Seriesof this district are usually thin and consist of shales, grits(frequently washed-up Skiddaw Slates and Volcanics) and grittyconglomerates with beds of dark limestone.

The comparative absence of conglomerates is striking in viewof the magnitude of the unconformity between the base andthe hard underlying rocks. Another feature of the junctionis its even character. The platform of older rocks must havebeen remarkably flat over an area of hundreds of square miles,as the Seventh Limestone was the first deposit on it not only inthe Whitehaven district, but also around the northern end ofthe Lake District.§

* C. EDMONDS, 1922, Geol; l\.Jag., PP. 120-21 ; E. DIXON, IgZ2, Summary of Progress for1921 (Mem. Geol- Surv.), pp, 53-4.

t B. SMITH, 1923. Summary of Progress for Ion (Mem. Geol, 5urv.), p. 66.t A. GILLIGAN. 1919. Abstr. Proc, Geol, Soc., No. 1031.§ K. W. EARLE, 1921, Abstr, Proc, Geol, SOC,)No. 1076, p. 10.

Sanguinoiites tricostatus ? (Po rt !.)Laxonema d . urei (F lem .)Murchisonia (Goniostrophia) d .

tatei DonaldPtychom-phalus d. atomaria (Phi ll.)Gastrioceras spp. nov. tGty-pbioceras reticulatuni (Phill .)Orthoceras aft. asciculare Brown

" morrisianum de Kon .P ericyclus d. virgatu s de Kon .Pleuronautilus sp. [near P . [alcatus

Salter non J. de C. Sow.]


MILLSTONE GRIT SERIES.

Resting upon the Snebro Gill Beds at Hensingham is th eUdale Coal, hitherto taken to be the lowest seam in the CoalMeasures. In Bedlam Gill it is associated with a black shalecontaining a goniatite fauna, indicating, according to Messrs .Bisat and Pringle, a Millstone Grit age. Similar fossiliferousshales overlie the Snebro Gill Beds in a mineral railway cuttingat Bigrigg farther south, where they are followed in upwardsequence by purple shales , sandy shales and felspathic grits .

FOSSILS FRO),I THE MILLSTONE GRIT SHALES.*

Lingula mytiloides ] . Sow.-Orbicutoidea nitida (Phill.)Productus sp.[semireticuiategroup]A uiculopecten losseni ? (von Koenen)Ctenodonta sinuosa (de R yckholt).L imatulina d. alternuta (McCoy) ,Nucutana attenuata (Flem.)Posidoniella minor (Brown)

lanns (Brown)" d. pyriformis Hind

Protoscbieodus axiniformi's (Port!.)Pterinopecten papyraceus (J. Sow.)Sanguinolites d . occidentalis Meek

and Worthen

Over the Workington-Whitehaven area exposures of thesebeds are rare, and st rata below the Four Foot Coal down to andbelow the Udale horizon are seldom penetrated by shafts andborings. Little is known of the fossils apart from those of thebeds just mentioned, and such evidence as exists points to apronounced development in places of grit or sandstone betweenthe horizons of the Four Foot and Udale seams, the remainderof the sediments being of Coal Measures type. So that, thoughthe Udale Coal makes a fairly satisfactory base, the top of theseries is still in doubt. Provisionally, chiefly because it isexpedient , the Four Foot Coal is considered to be the base of theCoal Measures.

COAL MEASURES.

The Coalfield, no less than the Ironfield in the LimestoneSeries, is broken and complicated by faults of considerablethrow. At Whitehaven in general, the measures dip westward,but towards the south the dip tends to swing to a more southwesterly direction, and a thick cover of post-Carboniferous rockssupervenes. This dip, being greater than the slope of the seabottom, enables the coals to be won with comparative safety.The workings of the Whitehaven Collieries extend seaward

• The cephalopods identified hy Mr. W. S. Bisat; the remainder by th e P aleontologicalDepartment .

t Several species are present; the type of one (G. crmu laluln Bisat , var. cumbriense Bisat)-comes from Bigrigg cutt ing. See p. 52, footnote.


Spiropteris sp.Sphenophyllum emarginatum Brongn.Lepidostrobus minus GradeLepidophyllum acuminaium Lesqx,Linopteris miinsieri (Eichw.)

for a. distance of over 4 miles from the coast-line. North ofWhitehaven the measures frequently dip inland and only take-on a pronounced westerly dip when the coast is reached.

The measures fall naturally into two divisions, the lowercontaining the chief seams of coal, and the upper with little or nocoal. The former consists of grey types of sediments commonto Lower and Middle Coal Measures of other coalfields; they arehere classed as Productive Measures. In the upper division theprevalent tint is purplish, shading to red, grey and brown.Sandstones usually predominate in the lower part of this division,certainly in the Whitehaven area (shales abound in the northerndistricts about Brayton and Aspatria), although the upper partcontains much shale and occasional beds of limestone withSpirorbis, thus linking these beds with the barren Upper CoalMeasures of the Midlands. This group* is known as the Whitehaven Sandstone Series. Near Whitehaven it has been provedto a thickness of 600 feet. Higher beds are denuded away.In the Brayton district the Series is over 1,000 feet in thickness. t

The sandstone varies in texture; usually it is a rough,fairly coarse and probably once felspathic sandstone, oftenhighly false-bedded, occurring in thick" posts" separated bythin irregular partings of shale. Mica is uncommon. Smallcakes or blebs of red shale or mudstone are included, sometimesso heavily charged with iron as to be mistaken for pebbles ofhrematite.

The limestones vary in thickness from about 2 feet to linesof small nodules, and in character from hard porcellanous creamylimestones with Spirorbis to calcareous sandy mudstone.

The widespread nature of the colouring of this series and theoccasional repeated alternations of red and grey rocks show thatmuch of the colour was original and that only in part is it dueto downward percolation from the Trias.

Sandstones of the lower part of the series are splendidlyexposed in the cliffs both north and south of Whitehaven. TheWest Pier of the Harbour is constructed of this stone.

FOSSILS FROM THE COAL MEASURES.t

Whitehaven Sandstone Series.N europteris heterophylia Brongn.

obliqua Brongn.rarinertns Bunbury

" microphylla Brongn.Mariopteris muricata Schloth.Eupecopteris sp.

• Mr. J. D. Kendall, in 1883, laid stress upon the unconformity at the base of this series (TheStructure of the Cumberland Coalfield, Trans. N. of Eng. Inst, Min. Eng., vol. xxxii, pp.-3'9"-356).

t B. SMITH, 1920, in Summary of Progress for '9'9 (Mem. Grot. Surv.), Appendix I, pp. 50-56.t Plants identified by Dr. Kidston ; the remainder by the PalaJontological Department.


Productive Measures.Alethopteris decurrens (Artis) Stigmaria ficoides (Sternb.)

" loncbitica [Schloth.) "reticulata Gopp.Annularia radiata Brongn. Lingula mytiloides J. Sow.Asterophyllites equiseti[ormis Carbonicola acuta (J. Sow.)

(Schloth.] ovalis ? (Mart.)Calamites suckowi Brongn. robusta. (J . de C. Sow.)Lepidodendron obovatum Sternb. d. subconstricta (J .Lepidostrobus sp. Sow.)Mariopteris beneckei Potonie Naiadites modiolaris (J . de C. Sow.)Neuropteris gigantea Sternb. Calacanthus elegans Newl.

" tenuijot ia (Schloth.) Rbizodopsis sauroides (Will.)Sphenopteris ct. obtusiloba Brongn.

Recent work tends to confirm the conclusion of Mr. J. D.Kendall, that the Whitehaven Sandstone Series is unconformableupon the Productive Measures. From the coast at 'Whitehavento about two miles inland the base of the Sandstone keeps.approximately 500 feet above the Main Band Coal, and, asexposed upon the beach near William Pit, Whitehaven, thejunction appears to be an upward passage from the ProductiveSeries. Inland, however, the upper series appears to transgressthe lower until the Whitehaven Sandstone and Main Band Coalare less than 300 feet apart, as proved by workings beneath alarge tract of Whitehaven Sandstone on Weddicar Rigg.* Theonly other explanation would imply a remarkable thinning of theintervening measures-a point which has not been proved orsuggested by available evidence. In a clear section at Brownrigg, near Arlecdon, the Whitehaven Sandstone rests sharplyand unevenly on the Productive Measures.

In the Whitehaven area the Productive Measures attain athickness of about 1,000 feet , measured from the Four FootCoaL The chief coal seams in this, in descending order, areas follows :-

Cleator Six Foot.Cleat or Four Foot. or Preston Isle Yard.Cleator F ive Foot, or China Bed,Bannock Band.Main Band.(Mussel Bed).Yard Band.Little Main or Two Foot Coal.Six Quarters Coal.Harrington Four Foot.

Numerous thin chance coals occur at many horizons.The measures consist of the usual assemblage of shales,

clays and sandstones with occasional ironstones, and many seamsof coal and fireclay. They do not differ materially from top tobottom, but are remarkably inconstant. This applies chieflyto the normal sediments, but taking the whole of the Cumberland

• T. EASTW OOO. 1922, in Summary of Progress for 19ZI (M em. Geol. Surv.), p. 61.


Coalfield into consideration, it applies no less to the coals themselves.

In general the sandstones are coarser in the lower part ofthe group: that above the Four Foot Coal often occurs asa rough grit with quartz fragments half an inch in diameter;that above the Six Quarter Coal as a coarse sugary sandstone;whilst those at higher horizons-above the Main Band, theBannock Band and the Cleator Six Foot-are usually of mediumgrain.

The only reliable index bed found to date is the MusselBed a few feet above the Yard Band. This consists, when welldeveloped, of a dark ironstone about one foot in thickness,closely packed with Carbonicola, but is frequently accompaniedor replaced (and this applies to the area south of Whitehaven)by smooth dark shales with scattered Carbonicola and heartshaped scales and other fish remains. Dark Carbonicola-shalesoccur at other horizons also', but form less reliable guides.

Definite marine bands are unknown. Lingula has beenfound at two horizons, viz., in the roof of a coal about zoft.belowthe Yard Band and in the roof of the China Bed, in each caseat one locality only.

The coals belong to the bituminous class suitable for household use, general steam raising, and also to some extent for coking. Individual seams vary in thickness and may be splitby partings. All are subject to' nips' and occasionally are wanting over hundreds of acres. In general the lower coals thin awaysouthwards while the upper seam') deteriorate in a northerlydirection.

The Four Foot Coal, worked at Harrington Collieries, isalmost valueless at Whitehaven, being either thin or split byshales.

The Six Quarters Coal is the most generally worked of theseams below the Main Band. North of Whitehaven it averages.about 3 feet of workable coal with a few inches of "rattler"or bastard cannel at the top. It crops out near Moresby Houseand other places in the Distington-Harrington area. Southof Whitehaven the main part of the seam is about 5 feet inthickness. It is wrought in the Haig Pit, Whitehaven, the recentdisaster having taken place in the under-sea workings in this seam.

The Little Main or Two Foot Coal is only about 2 ft. inthickness, but is frequently worked as it is of good quality. Theroof is of shale with a few inches of . rattler' at the top of thecoal, while the floor is a good fireclay.

The Yard Band, with two or three feet of coal, though sometimes worked, is not a high-grade seam. It crops out in severalparts of the district, with the Mussel Bed above it.

The Main Band, averaging five or six feet of coal, and inplaces attaining a thickness of ten to fifteen feet, is the mostPROC. GEOL. Assoc., VOL. XXXVI., Part I, 1925. 4


valuable seam in the district. It was doubtless one of the firstseams worked, the earliest regular workings dating from aboutI620. Some cannel is frequently present at the bottom of theseam. The roof is variable; it frequently consists of lightblue-grey mudstone with posts of sandstone. It crops out inmany parts of the district, the most regular" run " being on thewest side of the St. Bees-Whitehaven valley from SeldomSeen to Ginns.

It has been extensively mined from around Whitehavento the farthest extent of the under-sea workings and has beenwrought as far south as Hannah Moor, Rottington, in the concealed coalfield under St. Bees Headland.

The Bannock Band, frequently split by one or more partings,and yielding from five to six (north of Whitehaven) or from eightto ten (south of Whitehaven) feet of coal of fair quality, hasbeen wrought to less extent than the Main Band Coal at theprincipal collieries. It crops out with the latter seam at thefoot of the slope on the west side of the St. Bees-Whitehavenvalley. Although the actual basset is masked by Boulder Claythe seam is exposed in a number of dingles that trench the valleywall. Its roof is a black shale with fish scales. The overlyingsandstone, the Bannock Band Rock, is somewhat similar to thatabove the Main Band, except that it is in places of finer grainand of bluish-white tint. This rock appears upon the beachnorth of Lowca Point, and in the old quarry east of Walk Mill.

The seams above the Bannock Band are of less importance thanthose below, and are frequently split by partings of shale andclay. They and the measures between them are even morevariable and less easily recognisable than the seams below. Thebest section in this belt of strata is exposed in the quarry of the'Whitehaven Brick Co., about one mile south of Whitehaven,though smaller exposures may be noted in the cliffs and on thebeach both north and south of the harbour. Though the seamswere wrought in the early days of mining, they are not exploitedon a large scale, as a rule, at the present time.

CORRELATION AND INTERRELATIONS OF THE SUBDIVISIONS

OF THE CARBONIFEROUS.*Carboniferous Limestone Series.

The correlation with the development at Alston Moor andelsewhere is shown in the table on page 42. The beds belongalmost entirely to the highest zone (Dibunophyllum) of theAvonian,only the Seventh Limestone being referable to the sub-zoneimmediately below, that of Nematophyllum minus or the upperpart of 52.

• Chiefly by R.B.L.n.


On the other hand the Dibunophyllum Zone of Cumberlandincludes limestones of higher horizon than D, or D"3, whichfor our purpose may be regarded as the highest in the SouthWestern Province. The classification of D-limestones higherthan D, .is not at present satisfactory, and is being dealt withby a committee of the British Association. It is unnecessary,therefore, to discuss here the various suggestions that have beenmade further than to remark on the use of Dv in the table, asagainst D3.

It has been established, by the work of Vaughan*, Garwood]and Stanley Smith'[ especially, that the Carboniferous Limestoneof the North of England includes horizons higher than can belegitimately referred to D2 or D"3, and, if they are retained inthe D-zone, it seems natural to group them as D 3. Unfortunately D3 was established for a " zaphrentid-phase " locallydeveloped at the top of the Carboniferous Limestone in Irelandand elsewhere, whereas the high-zonal fauna of the North ofEngland is a " standard" one. The standard limestones above D,have, accordingly, been grouped as Dv, the relationship ofwhich to D3 is defined by Vaughan§ thus:-

"Dy constitutes the continuation and apotheosis of the earlier D2fauna; it is typically expressed in the fauna of the 'Main Limestone'of the' Yoredales ' [the First Limestone of W. Cumberland]. D3 connotesa phasal fauna later than the beginning of D2, and contemporaneous, inpart, with Dv."

As Vaughan has delimited D; Irom Ds., in Northumberland]at the base of the Great (or Main) Limestone, and as the faunawhich he cites in support characterises our First Limestone and isabsent from those below, it is deemed best, pending the reportof the committee mentioned above, to group-the First Limestoneand higher beds of the Carboniferous Limestone Series as Dv.

It should be noticed that Dv does not include the wholeof the Yoredales. Garwood has shown'[ that the Yoredalesextend down to the base of D2 , and he divides them into anUpper and a Lower group, the former being Dv,Millstone Grit Series.

We have spoken of the uncertainty attaching to the classification of the top beds of the Avonian, but when we come to thestrata immediately above we enter a region of chaos. The reasonfor this is more obvious than a way out of the chaos, and is tobe found in the changing conditions of sedimentation, from

• A. VAUGHAN, 1910, Rep. Brit, Assoc. for 1909, pp. 3-5 (of abstract), table III ; in S. SMITH,1910, Trans. Nat. Hist, Soc. Northd., etc., n.s., vol. iii, pp. 600-2 ; and 1915, Quart. journ.Ceol. Soc., vol. lxxi, pp, 3O-~I.

t E. J. GARWOOD, 1907, Geol, Mag., pp. 73-4; and 1912, Qua,t./ourn. Geol. Soc. vol.lxviii.,pp. 545, 547·

t S. SMITH, 1910, see VAUGHAN, footnote; 1915, Quart. ]ourn. Geel. Soc_, voi, lxxi ,po 218;1916, ibid., vol. Ixxii, p. 280.

§ A. VAUGHAN, IgIO, p. 3 of abstract and table II.I! In S. SMITH, IgIO, pp. 598-600.~ E. J. GARWOOD, 1907, p. 73; '912, p. 540.


those, dominantly marine and limy, of the Lower Carboniferousto the continental regime of the Upper Carboniferous sandstonesand argillaceous beds. The change was not synchronous overthe whole country, and it was preceded in places by upheavaland denudation. Further, although it brought about greatalterations in flora and fauna, some of these appear to havelagged more or less after the physiographic change. Hence thevarious conflicting classifications based on lithological and palseontological grounds. The stratigraphist hopes to set all in orderby a study of sedimentation and earth-movements; and greatthings are expected of the intensive study of the goniatites initiated by Wheelton Hind and ably carried on by Bisat and bythe Manchester unit of the Geological Survey.*

So far as the West Cumberland deposits are concerned, weare happily spared a great deal of worry; a merciful Providencehas removed a large part of the sequence. Above the FirstLimestone no great thickness of beds intervenes before the lowestgoniatite-horizon present in this district is encountered. Thishas yielded Gastrioceras crenulatum Bisat, var. cumbriense Bisat,found also near the top of the Millstone Grit of Lancashire.']Its correlation with the upper part of the Millstone Gritaccords with the incoming of Westphalian Coal Measures atno great distance above the Cumberland goniatite-bed.

What of the relations of the beds below, i.e., the HensinghamGrit and the Snebro Gill Beds, between the First Limestoneand the Gastrioceras-shales? The Hensingham Grit has thelithological character of Millstone Grit, whence it has hithertobeen regarded as such. But in this character it is closely comparable with the Orebank Sandstone of the northern part of thedistrict (Cockermouth) which is unquestionably Avonian. TheSnebroGill Beds are linked with the Avonian by the facies oftheir fauna, which includes crinoids and brachiopods, and Mr.Pringle has found further evidence of such relationship in thevertical range elsewhere of some of the species. In one respect,however, the verdict of these species is not unanimous, forPleuronautilus nodosocarinatus is recorded from undoubted Millstone Grit (Cayton Gill Beds) in Yorkshire.] But the balance ofevidence favours an Avonian age, and some ofthe beds maybe compared in their cherty character, due to an abundance of siliceoussponge-spicules, with the cherts in the Yoredale Beds of Swaledale.

As the Cayton Gill Beds are low in the Millstone Grit itis difficult on either view to avoid the conclusion that a markedhiatus separates the Snebro Gill Beds from the Gastriocerasshales, which overlie them almost immediately. Such a hiatus,however, need cause no surprise. It merely brings Cumberland

• Since this was written Bisat has published valuable work (Proc. Yorks. Geol. Soc., vol. xx ,1923-4, pp. 40-124), which goes a long way towards reducing the chaos to order.

tId. B1SAT, 1923-4 p. 122.: W. BISAT, 1914, Proc, Yorks. Geol,Soc., vol. xix, p. 20, table III.


into line with Scotland,* Northumberland] (unconformitypossibly local), the dale country.] and other parts of Britain§where evidences of an unconformity or unconformities at or nearthe junction of Lower and Upper Carboniferous have beenaccumulating for some years past.

Coal Measures.

Owing to the unfossiliferous character of many of the beds,the subdivisions of the Coal Measures established on palreobotanical grounds by the classic work of Kidston] and recognisedby him at Canonbie.f just over the Scottish border, cannot bedelimited from one another with precision. Lower Coal Measures,which are included by Kidston with Millstone Grit in theLan ark ian, are doubtless present, as the sequence from theGastrioceras-shales upward to the Productive Measures is aconformable one, but beds with a Lanarkian flora have notbeen recognised. The Productive Measures have a Westphalianor Middle Coal Measure flora,** and as the highest of them haveyielded a plant that has been recognised by Kidston as Sphenophyllum emarginatum Brongn., a Transition Coal Measure form,it may be inferred that they extend to the top of the Middlesubdivision or to the base of the Staffordian or Transition CoalMeasures. The lower part of the Whitehaven Sandstone isshown both by its flora and by it." lithological character to belongto the Transition Coal Measures, the special features of whichare now well known from the works of Dr. Walcot Gibson.j ]

* C. H. DINHAM, 1913, in Summary of Progress for 1912 (llJem. Geol. SUfV.), pp- 61-2 ; and1921, in The Economic Geology of the Central Coalfield of Scotland, Area IX., Carluke,etc. (JJem. GeQ!.Surv. Scot.), pp. 764, pI. V. ; G. V.WILSO", 1914, in Summary of Progress for 1913,l'p. 59-60, fig. 7.

t R. G. CARRUTHERS, 1923, in Summary of Progress for 1922, p. 73, fig. 5.t Mr. BISAT has pointed out (The Physiography of North Britain in Millstone Grit Times,

.Naturalist, 1921, p. 131) that much evidence already available suggests a non-sequence at thebase of the Mi.lstone Grit in Yorkshire, and a similar break" over a large area in the northern-parts of Britain, including Scotland," has been in the mind of J. G. GOODCHILD (Victoria CountyHistories-Cumberland, Geology, Ig01, p. ~8). The existence of an unconfonnity there basnow been defiinitely proved by detailed mapping near Grassington and to the north (Bishopdaleand Wensleydale) by Messrs. R. G. S. HUDSON and L. ]. CHUBB and in Upper Nidderdale byMr. L. H. TONKS (Naturalist, 19~3, p, 306). These investigations are now being completed forpublication. One of us is indebted to Messrs. Hunsox and CHUBB for demonstrating the evidencenorth of Grassington. (But see also Bisat 1923-4.)

§ In S. Wales and Mon. :-0. T. JONES, 1907, in Summary of Progress for 1905, p. 53; and1914. in The Country around Haverfordwest, Mem; Geol, Surv., p. 151 ; E. DIXON, 1909, in TheCountry around Newport, Mem, Geol. Surv., ed. 2, p. 20; and Ig:n, Geol. Mag., p. 157 tifton(Mon.) and Abergavenny] : and F. DIXEY and T. F. SIBLY, 1918, Quart. [owm: Geol; Scc., vol.Ixxiii, p. III [Newport'[.,

In the following cases the beds above the unconformity are Coal Measures :-T. F. 5IBLY,1912, Geol. ]4ag., p. 420 [Forest of Dean]; E. DIXON, IgII, Rep. Brit. Assoc. for 1910, p. 611,and 1917, Trans. Roy. Soc. Edin., vol. Ii., p. 1067 [Titterstone Clee Hill]; L. M. PARSONS, 1919,Geol: Mag., p. 79 [Coalbrookdale] ; WICKHAM KING and W. ]. LEWIS, 1914, Rep. Brit. Assoc •.for 1913, p"'48z, and W. KING, 1921, Trans. lnst. llfitz,. Eng., vol. bd., pp. 161-3, and in lit. [5.Staffs.].

II R. KIDSTO~, 1894, Proc, Roy. Phys. Soc., Edin., vol. xii., P. 183, and 1905, Quart. Iourn,Geol, Soc., vol, lxi, p. 308.

'Il R. KlD~TO", 1903, Trans. Roy. Soc;Edin., vol. xl, p. 741.** First recognised in this district by Dr. E. A. Newell Arber, 1903, Quatl. Journ. GeoI. Soc.,

vol, Iix, pp. 1-24.tt \VALCOT GIBSON, 1901, Quart.]ourn. Geol. Soc., vol. lvii., p. 251.


In resting unconformably on the underlying measures it resemblesthe Transition or Upper Measures of North Wales,* Coalbrookdale[, Wyre Forest ], etc.§

The thickness, amounting to 1,000 feet or so, of the ProductiveCoal Measures of the Whiteha ven field is far less than the2,00o--4,00oft. usually found where the Coal Measures areunderlain conformably by Millstone Grit, as in Northumberland.Yorkshire, Lancashire and North Staffordshire. In this respectthey are comparable with the Middle Measures of North Wales(1200 ft.)I! where again Millstone Grit is present, and with thoseof South Staffordshire and Warwickshire (400-1200ft.) near thesouthern margin of the great basin of the coalfields of the Midlandsand Northern England. In South Staffordshire and Warwickshire, however, true Millstone Grit is absent and the CoalMeasures rest unconformably on older rocks.

NEW RED SERIES.

The attempts to separate the New Red Series of West Cumberland into Permian and Trias, and the various changes in correlation that have been made, are due in great measure to theabnormal character of the sediments involved. A discussionof this subject has appeared recently'[ and the following is a briefresume of the conclusions reached.

The Brockram, Magnesian Limestone and succeeding St.Bees Gypseous Shales all pass laterally into a continuous massof brockram when traced inland from the coast.** Layers ofbrockram also occur in the base of the St. Bees Sandstone, whichsucceeds the shales conformably.

The brockram appears to have been formed under arid continental conditions throughout, and consists of a series of flatlying, overlapping, torrential fans, shot out from a numberof canons or gullies in the eastern mountain range, bordering aplain with somewhat irregular surface, composed in the mainof tilted and denuded Carboniferous rocks, which have furnishedtheir quota also to the deposit. At some distance from the mountains the plain held an inland sea in which the Magnesian Limestone and the succeeding gypsiferous shales were depositedconcurrently with the formation of brockram.

'" C. B.WEDD, 1913, in Summary of Progress for 1912, pp. 15-r6 ;1914, in ditto for 1913, p , I 6;and 1924. in Geology of Flint, Hawarden, and Caergwrle, pp. 17. 43. 132-7 (Mems. Geol. 5urv.).

t M. W. T. SCOTT. 1861. Quart. [ourn: Geol.Soc., vol. xvii, p. 457; D. JONE,. 1871, Geol,Mag.,p. 200; and W. ]. CLARKE, 19°1, Quart. Iourn, Geol. Soc., vol. lvii, p. 86.

t D. JONES and 'V. ]. CLARKE, op, cit.; E. A. NEWELL ARBER, 1914, Phil. Trane., ser, B,vol. 204, p. 363; and E. DIXON. work not yet published.

§ In S. Wales unconformity between the Westphalian and the Staffordian has been suggestedby DAVID DAVIES, 1921 (Rep. Brit. Assoc. for 1920, p. 358, and Quart. [ourn; Geol. Soc., vol.Ixxvi., pp. 68-71), a view which receives further support from the work of R. DAVIES andA. H. Cox (1922, Proc. S. Wales Inst, Eng., vol. xxxvlii, p. 41, and discussion, pp. 334-5.)

lie. B. WEDD. i" lit.~ B. SMITH, 1924. On the West Cumberland Brockram and its Associated Rocks. Geol, Mag.,

pp. 28<r-308.** Summary of Progress for 19Z1 (21[~m. Geol . Sur'c.), 1922, p 62.

P LATE 7.

Plwto H .M . Geological Surv ey.

A .-BROCKRAM ON ' V HlTEHAVE N SAN DSTONE, BARROWMOU TH .

Magnesian Limestone in background.

PIw/() H .M . Geologkal S"rvey.

B.-STRIATED GLACIAL P AVEMEl'i T: H E NSI NG HAM GRIT.

BARFS SILI CA QUARRY, NEAR D ISTINGTON (see p. 62) .

[To [a ce p. 55.


As time went on the shallow waters encroached steadily uponthe land and the St. Bees Sandstone was laid down. Mostof its material probably came from outside sources.

The St. Bees Sandstone passes upwards into a thick series,mostly of shale-less sandstones, which is correlated" with theKirklinton Sandstone of the Carlisle District.

Typical sections of the Brockram, Magnesian Limestone,St. Bees Shales and Sandstone occur in the Headland of St.Bees, the classic section of the first two occurring on the beachnear Barrowmouth IPi. 7), where the sequence is as follows :-

Ft.Red shales with gypsum, obscured by slipsThin limestones and shales 3Shales wrth thin limestones 3Limestone, with breccia fragments in lowest foot.. 10

Brockram, Sins. to 6Unconformable on Whitehaven Sandstone.

Inland the Magnesian Limestone and St. Bees Shales thickensomewhat but begin to give place to brockram to the east of theSt. Bees-Whitehaven valley, where the Limestone is reducedto zft. and less, and an upper brockram is developed at the expense of some of the St. Bees Shales. Both Limestone andShales finally go out altogether] and we are left with St. BeesSandstone, resting directly upon brockram to a maximumthickness of 400 feet.

At Barrowmouth the brockram overlies the WhitehavenSandstone Series, but inland it transgresses the Productive CoalMeasures, the Millstone Grit and the Carboniferous LimestoneSeries, and finally comes to rest upon the underlying volcanicrocks in the ground south of Egremont and east of Hale. Itvaries in character and composition from point to point, herecontaining much Carboniferous Limestone, there very little;at one point being fine-textured, with sandy or shaly layers,at another coarse ,and rough. The stones vary from angularto subangular in shape and are set in a muddy or gritty matrix;the whole deposit is roughly stratified and appears as a series ofsuccessive" posts."

On the coast the Magnesian Limestone is a fossiliferousyellowish-grey rock frequently of honey-combed appearance.Inland it is grey-brown and crystalline, blue-grey or pinkish,but varies considerably in texture, in places being smooth-grained.

The St. Bees Shales are frequently marly and nodular andat Barrowmouth contain a bed of massive gypsum which hasbeen exploited.] Gypsum has been proved by bores at otherpoints about St. Bees Headland.

• This correlation was first suggested by Prof. J. w.Gregory in 1915, A Deep Bore at Seascale in Cumberland, Geol. Mag., p. 149.

t Summary of Progress for 1921 UHe1J1. Geol, SUfV.), 1922, p. 62.t Gypsum and Anhydrite, vol. iii. of Special Reports on the Mineral Resources of Great

Britain (Mem. Geol; Sur".), rgI8, p. IS.


Good sections of St. Bees Sandstone are exposed along thecliff-road at Barrowmouth, and in Messrs. McKay's Quarries on thecliff top. It consists of fine-grained, laminated, micaceous, ripplemarked red sandstones with way-boards of red shale and a numberof pale grey to greenish-blue bands of sandstone.

Farther south it passes up, by imperceptible stages, into theabove-mentioned nearly shale-less red sandstones, which, however, contain a few beds of shale and pale bands or patches ofsandstone. The texture is little coarser, much of it is no coarser,than that of the St. Bees Sandstone, but near Calder Bridgeit includes 100ft. or more of sandstone with many coarser layersfull of wind-blown grains-a feature which serves to link it upwith the Kirklinton Sandstone. At Seascale a combined thickness of 3,I80ft.* of the two sandstones was bored throughwithout reaching the base.

On palseontological grounds the Magnesian Limestone isconsidered to be of Permian age, whilst the St. Bees and Kirklinton Sandstones are generally taken to be Trias (Bunter). TheSt. Bees Shales appear to form an intermediate group.

Similarly the brockram, where fully developed, must beconsidered to belong to both systems; and its character seemsto show that the climatic conditions were constant during theperiod of its formation.

THE GLACIAL PERIOD.

The Glacial deposits of the Whitehaven district are extensiveand varied. If they could be read aright, the changing events'that took place during their formation would form a story littleless fascinating than that unfolded by Goodchild in Edenside,Much work, however, remains to be done before the mode offormation of many of the deposits is known, and, if we may beguided by the development of opinion in glacial matters elsewhere, a vastly longer period must elapse before the interpretation is generally accepted.

Certain broad facts have long been known; they are part ofour heritage from Mackintosh, Goodchild, Kendall and others.It is clear that during the period, or periods, of maximum glaciation a broad flood of ice swept south-eastward from Criffel andother high ground in S.W. Scotland, and that it split itself againstthe fells somewhere north of Cockermouth, one stream to goup the Vale of Eden and so across Stainrnoor to the east, theother to turn southward along the coast. The site of the iceparting is unknown. If, as is possible, the glacial deposits thatare known to us have been formed during the wane of ice-sheets,and throw no direct light on the movement of the ice at maximum glaciation, it is unlikely that the site ever will be known.

• J. W. GREGORY, 1915, A Deep Bore at Seascale in Cumberland, Geol. Mug., pp. 146-7.

PLATE 8,

""-'-'-'-

.- '-'-'

/._. ,. . - .

» :00,,"

j "\". ......... :..::= ._._..,.... . -.s~_ . ""

( 0 ,-.--. \ '\) .'\ < .. \

\ .. ....\ .. '-. .........

'- '-'-DEPOSITS OF LAKE DISTRICT I C E - CA P .

D, E:SKE:R -~R OUTWASH-DELTA (!) }MOCKE:RK INK I RREGULAR KAME: . TARN- KP

\. F ' OUTWASH - FAN . PAUSE: .

F :>.. . O r I.AMPLUGH PAUSE .

F e . .. FeEDING -eSKER .

'_.",,'

Ra ise -<-,.-._.-;[

D E POSITS O F IRISH SEA ICE -SHEET/ f '- N EAR LAI( £ ENNERDALE.

0 " / ' - '----'_ , 0 0 0°' RC~ - IS TILL WHERE PROVED .

. _ .9 0, .f T/If SUPPOSED TERMINAL MORAINE.-.i.-..L.....~LJ_~_~--'-_-'-_---' ---.;·:.------="'- .L_ -'- _

>4-,

ALLUVIUM & ALLUVIAL F ANS.

( O L D E-R ) .

LAMINATED C LAY .

/ Hig h/' .... ...,

~:..;C;"

DEPOSITS OF G LACI£.R-LAKE: £.NNERDAL£..

:-:-d: :': 600FT, D E.I..T A (NEWER).

~~ :':~J:::: 7 0 0 -FT.

ii?J?}/ 700 +FT.

~+:a:::++ 800 FT.

INDEXCREST OF ESKER

• SHALL-OW C HA NN£L}OF Gl..ACIFLUV.:::::::::::::::: D£f:.P t- -IAL STREAM .~OVERFLOW .."IIIIII/ ICE -CO N TACT 81..0 PE .

, P OS I T I O N OF I" R ON T 01" 1...0 . ICE--'" ( B R OK E N WH E R E UNCERTAIN)'....__' DI T TO ( APPROX)P£.RIOO OF800FT. LAK£

~ LIMIT,s OF TERMINAL MORAINE,

............... ( B ROK E N WHERE, UNCERTAIN).

W 'T. H l~,) l r .

MAP SHOWING STAGES IN THE RETREAT OF THE LAKE DISTRICT ICE-CAP IN THE ENNERDALE AREA.

[To face p. 57.


The southward-flowing ice-stream was flanked, and doubtlessin part fended off from the fells, by the ice descending from theLake District. Along the line of contact-the battle-frontwhere the two ice-fields contended for mastery-the LakeDistrict ice-streams would have no alternative but eventuallyto turn southward also.

The deposits of Boulder Clay and gravel appear to have beenformed largely, if not wholly, at a period, or periods, when theactive streams outlined above had given place to two waningmasses of ice, the one-a great sheet much larger than theother-still pressing landward from the Irish Sea basin, the othercapping the Lake District fells and, for a time, descending tomeet the Irish Sea ice-sheet on the coastal plain. The BoulderClay, fashioned beneath and in the ice, first saw the light as theice-fronts receded. Of the gravel and sand, which were waterdeposited, the thin impersistent masses embedded in the tillmay well have been subglacial or englacial also, like the BoulderClay, but the large areas are now believed to have originatedextra-glacially, as fans or deltas, or similar but irregular outwashdeposits, where subglacial streams have emerged at the ice-front.

The Boulder Clay in places forms an irregular sheet mantlingthe" solid" rocks and doing its worst to obscure their features;in others it has been fashioned into drumlins. The massesof sand and gravel include kames and eskers, besides manyundefined bodies whose relationship to the ice-front is notsuggested by form or other evidence.

The kames are mounds more or less elongated along an icefront line.* Kames close-spaced laterally form a i' kame-belt"(often called a moraine) and may thus enable an ice-front line tobetraced without hesitation for several miles (see Plate 8).t

The general form of the ridges known as eskers is too wellknown to need description here, but a few words may be saidabout their origin. Of this the chief theories are :

(I) They have been deposited along subglacial or englacial streams and may, in fact, be regarded as casts of theice-hemmed channels of such streams;

(2) " Eskers are the deltaic deposits of glacial rivers andtheir ridged form is due to their continuous deposition at suecessive positions by the slow recession of the river mouth duringthe retreat of the ice sheet.Y]

The second theory, which as Prof. Gregory mentions, wasadvocated almost simultaneously by Hershey,§ de Ceer] and

* Le., the course of a stationary ice-front, this being a translation of nisrandslinje" suggestedby De Geer (in lit.).

t E. E. L. DIXON, 1922, Summary of Progress for 1921 (Mem. Geoi. SUrl")' p. 121, fig. 5.:: ]. W. GREGORY, 19201 The Irish Eskers, Phil. Trans., ser. B., vol. 210, p. 115. The quota.

tion is made as being a concise statement of the second theory and no adherence to it by Prof.Gregory is implied.

§ HERSHEY, r897, Amer. Geol., vol. xix, pp. 197, 237.ft DE GEER, 1897, Geol. For. F orb. Stockholm, vol. xix, p. 366.


von To11,* accords the better with the known facts. An eskermay therefore be likened, somewhat crudely, to a trail of riceleft on the ground when a punctured bagful is dragged slowlyin one direction.

Further, both being deltaic, the distinction between kamesand eskers would appear to resolve itself largely into one of elongation along or at right angles to the ice-front.

Closely related to kames and eskers are esker-deltas and eskerfans, outwash-deltas and outwash-fans. At the risk of overburdening an already super-voluminous literature these terms haverecently been suggested or re-defined] to connote deltas and fans(s.e., subaqueous and subaerial deposits) which in the one caseare in obvious genetic connection with an esker (" feeding-esker ")or, in the other (outwash-deltas and fans), whilst unrelated toany esker, show by their form that they have been depositedagainst a stationary ice-front by an emerging sub-glacial stream.The elements of topographical form that are of most use in therecognition of deltas and fans of both classes are: (1) a lobatefrontal margin of the fore-set beds in the case of deltas; and(2) a steep and linear" ice-contact slope" or back-slope, i.e., themore or Iess degraded surface of contact between the delta orfan and the ice against which it was banked.

To continue the simile of the damaged rice-bag, if the dragging be stopped at intervals so that the rice accummulates in anumber of little heaps connected by the trail, like beads on astring, the heaps correspond, it is supposed, to the esker-deltasor esker-fans and the trail to the feeding-esker of a completesystem.

The foregoing explanation of some of the deposits has beengiven in some fulness because the nomenclature is, in this country,comparatively new. Other deposits of equal importance indetermining the physiography in glacial times, such as morainesand varve-clays, are, however, also represented in the district.

Here, as elsewhere, a tripartite disposition 'into "UpperBoulder Clay:' "Middle Sands and Gravels" and "LowerBoulder Clay" has been found in places. To be complete itshould be capped by " Upper Sands and Gravels," but these aregenerally wanting. The succession of boulder clays demonstrates re-advance of the ice over the Middle Sands and Gravels(deposited extra-glacially during retreat), and the re-advance mayhave been repeated. But whether the interval of amelioratedclimate, indicated by the retreat that preceded the re-advance,should be called an inter-glacial period or was merely a glaciation-interval.] is at present unknown. At St. Bees (p. 60)

* VON TOLL, I8g8, Sitz. Nalu,j.-ges. bei Univ. J",jew (Dorpa!), vol. xii, p, I.t E. E. L. D,XON, Ig'2, p. lI8.t D. \VOOLACOTT, 1921, Geol, Mag., p. 21..


a temperate-climate peat has been found with sands and I02msbelow what appears to be Upper Boulder Clay.

Glaciated rock-pavements are not often seen, but a particularly fine example is shown on PI. 7B.

The conditions-the impingement of an invading ice-sheetupon a deeply-dissected upland-were eminently favourable tothe production of ice-dammed lakes in the valleys, similar tothe classic examples of Glen Roy and Cleveland described byJamieson and P. F. Kendall.

An instance, that of the Whicharn valley lake describedbelow, was brought to notice some years ago,* and in the samearea other evidence of the invasion of the lower part of theouter slopes of the fells by the Irish Sea ice was unmistakeablyrecognised in "marginal channels" and" in-and-outs."

In the area dominated by Black Combe, the whole districtwas over-ridden by an ice-sheet formed by the confluence ofthe edge of the Irish Sea ice and the Lake District ice-cap, oneof the points of contact between the two lying about a milewest of Black Combe summit.

Details of the ice-movement in this area between Eskdaleand the Duddon estuary have been given elsewhere. t

It will suffice to note here that ice-streams descending fromthe Lake District valleys added their share to the fringe of theIrish Sea ice-sheet and travelled down the coast alongside itand one another, each preserving its identity for a time.

After the period of maximum glaciation, represented by aLower Boulder Clay, a period of shrinkage and melting commencedand the Lake District and Irish Sea ice parted company, theformer retiring inland, the latter retreating seaward.

During this stage the first deposits exposed or formed weretrails of boulders, moraines (of which a good example occurshalf a mile E. by S. of High Corney) and shelves of stony clayof a morainic type. These were succeeded by deposits of gravelwith sand formed either as a marginal fringe to the retreatingIrish Sea ice or in lakes or lakelets held up by it in hillside ernbayments. The gravels were partially destroyed and trenched by aseries of marginal channels, of which those near Bootle andCorney are examples.

At about this period the Whicharn valley, near Silecroft ,held a glacial lake that drained across the volcanic rocks northof Millorn into the Duddon, which also held a fluctuating lakedrained by overflows across Low Furness into .MorecambeBay·t

'" B. S,nT1f, 1912, The Glaciation of the Black Combe Dlstric t, Quart. [ourn, Geol, 5-)(.,vel. Ixviii , pp. 402-48, PIs. XLI.-XLIIJ.

t B. S:UITH, loco cit.::: C. GRACE and F. H. SMITR, Some Observations on the Glacial Geology of Furness, Proc,

Yorks. Geoi. Soc., vol. xix, 1921-2, PP. 4°1-419.


The Whicharn valley lake-the first known example of animportant lake formed in an ice-dammed valley on this coastline-is now known to have been but one of a suite occupyingthe main valleys of West Cumberland. The glacial lakes of theDuddon and Ennerdale (see below) have been since detectedand described, and it seems probable that the marginal channelsof the Bootle district were mainly cut by waters dammed up in,and escaping from Eskdale. Doubtless the Miterdale andWastwater valleys also held large bodies of water at this stage,for amongst other suggestive phenomena there are gravels ofdeltaic type on the slopes of Irton and Muncaster Fells and twowell-marked overflows across Muncaster Fell, the first at approximately 400 feet, the other 2 miles farther west at a little below300 feet.

The channels near and north of Bootle are cut (a) in a shelflike part of the western outcrop of the Eskdale Granite, slopinggently from near 500 feet to 300 feet above sea-level, fromwhich it drops abruptly to the 200 feet level; and (b) in theVolcanic rocks near Bootle, together with those parts of thegranite and Skiddaw Slates which immediately bound it on thenorth and south.

Two or more courses were sometimes formed in parallel sequenceat consecutively lower levels. "In-and-out" channels, andchannels formed entirely in drift, or between an ice-wall anda rock- or drift-wall, are also represented.

To the west of the above-mentioned channels the BoulderClay-covered plain (underlain by New Red Sandstone, muchof which is below present sea-level) was overspread by sand andgravel with subordinate beds of clay; these deposits appear tohave been formed during the period which succeeded the cuttingof the lowest undoubted marginal channels.

There then seems to have been a re-advance of the ice from theIrish sea basin and a thin upper Boulder Clay, similar to thatof St. Bees, was deposited on the sands and gravels along thecoastal margin. This re-advance, however, spent its force beforethe ice reached the hills.

Although boulders of Criffel and other Scotch granites arepresent fairly commonly all down this coast, no example of therock of Ailsa Craig has been recorded. Several small pebblesof this rock, however, were discovered on Silecroft beach abouttwo years ago by Prof. A. Gilligan, of Leeds.

On the coast at St. Bees a Lower Boulder Clay is overlain by aseries of sands and gravels that form the hummocky ground atthe mouth of the valley. Here and there the gravels are cappedby either one or two beds of peat with associated sands and loams ;and at one point a pale red upper clay was found resting upondisturbed and contorted beds of peat, the thrust being from

GEOLOGY OF THE WHITEHAVEN DISTRICT. 6r

seaward-thus seeming to prove that these peats are interglacial.*An examination of the plant-remains by Miss M. E. ]. Chandlersuggests that the climate of this period of peat formation wasvery little colder than that of the Lake District at present.

To the south of the embouchure of the Pow Beck the UpperBoulder Clay covers a considerable tract of the "Middle Gravels "and abuts against a rising slope of St. Bees Sandstone, at thefoot of which a marginal drainage channel from the St. Bees valleyis well displayed. Upon the top of the slope some patches ofgravelly material represent "Upper Sands and Gravels," connected with the retreat of the ice that formed the Upper BoulderClay.

The glacial phenomena in the Ennerdale area (Plate 8) havebeen described] recently, and the following conclusions reached:

"I. Towards the end of the Glacial Period the Lake District icecap shrank away from the Irish Sea ice-sheet along a line at presentunlocalised, which lay along, or west of, the Marron River aboveUllock.

2. During its retreat the ice-cap paused along the line Mockerkin TarnKirkland, and later at the foot of the fells at Lamplugh, at each pausedepositing kames but no other form of recessional moraine.

3. The Mockerkin Tarn-Kirkland kame-belt includes outwashfans and probably outwash- and esker-deltas, the deposits, subaerial andsubaqueous respectively, of more or less persistent subglacial streams.The supposed deltas: suggest that water was standing in the Marronvalley at about 400 ft.

4. The few eskers also present make wide angles with the line ofice-front and mark the courses of subglacial streams.

5. Buring the Mockerkin Tarn-Kirkland pause water was impounded as a glacier-lake by the Irish Sea ice in Ennerdale to a heightof 600 ft., its outlet being to the south between Dent and Flat Fell.

6. The Lamplugh kame is an outwash-fan of a great subglacial streamthat has debouched at a height of about 1,000 feet from a wall-like icefront across the Wisenholme and Rakegill Becks. The country immediately to the west, down to 700 feet at least, was not under waterwhen the fan was formed.

7. Later, but probably while the ice-front still lay in the same position, the level of glacier-lake Ennerdale was raised to 800 feet, and thelake spread over the foot of the fells to the north as far as Lamplugh,The ice-cap still covered the fells, but had disappeared from Lower Ennerdale, possibly owing to flotation of its ice as bergs by the lake-water.

8. The cause of the rise of the lake-level from 600 feet to 800 feetwas a re-advance of the Irish Sea ice, which closed the outlet of the lakeat the lower level.

9. This re-advance mayor may not have been due to relief from thecounter-pressure of the Lake District ice-cap.

IO. Still later the lake-level fell by stages to 600 feet again. Presumably renewed retreat of the Irish Sea ice disclosed lower outlets downto that formerly used.§

• B. SMITH, 1922, in Summary of Progress for 1921 (Mem. Geol, SurJ.), pp. 67-8.t E. E. L. DIXON, 1922, lac. cit., p. lIB.: The' delta' nature of these kames has been confumed by subsequent work.§ One of these, just under 700ft., has subsequently been found by Mr. Hollingworth between

Flat Fell and Blakeley Raise.

62 BY THE DIRECTORS,

II. The most obvious deposits in the glacier-lake are the deltas of:glacier-fed streams.

12. Ennerdale Water is presumably dammed by the Drift, apparently aterminal moraine, deposited by a lobe of Irish Sea ice upon its re-advancc."

This story is continued south of the Ehen valley wherea series of gravel deltas have been mapped.

Near Standing Stones deltaic material of exclusively LakeDistrict origin was deposited in a lake at about 875 ft. O.D.

Near Cockhow at over 700 ft., and westward at lower levels,gravel deltas were thrown out from Irish Sea ice into lakes,the waters of which have escaped by a series of marginal anddirect overflows converging on Uldale (PI. 9B).*

EXCURSION TO THE WHITEHAVEN DISTRICT.

SATURDAY, JULY 26TH, TO FRIDAY, AUG. 1ST, 1924.

Directors: BERNARD SMITH, M.A., D.Se., E. E. L. DIXON,A.R.C.Se., B.Se., T. EASTWOOD, A.R.C.Se., C. EDMONDS,AND S. E. HOLLINGWORTH, B.A., B.Se.

REPORT BY THE DIRECTORS.

SATURDAY, JULY 26TH, 1924.

Leader: T. EASTWOOD.

THE party proceeded to Distington by bus to inspect the fractureddome of the Lower Carboniferous rocks forming the Barfs inlieron the north-west of the village. A large disused quarry in theFirst (or highest) Limestone was visited; the wavy character ofthe bedding was noticed, and a few fossils, together. with somebarytes, were collected. The cover on most of the quarry isBoulder Clay, but near the limekilns Hensingham Grit succeedsthe First Limestone.

By the courtesy of Mr. T. Fletcher, Barfs Silica Quarries atWest Gill End were next visited. The large quarry is inHensingham Grit of variable grain, and evidently at one timean arkose, though the felspar is now completely kaolinised.Baring operations in this quarry have revealed the finest glaciatedpavement so far discovered in West Cumberland (PI. 7B). Thestriee range N.N.E.-S.S.W., following the drumlin ridges seen tothe north, which contain Lake District and local rocks. To thesouth-west the Hensingham Grit is terminated by a down throwfault seen in a quarry, in which are exposed highly disturbed shales,sandstones, ganisters and occasional dark earthy limestonescarrying fossils, which indicate that the measures belong to the

• s..E. HOLLINGWORTH in Summary of Progress for 1923 (Me.... Geol. Surv.), pp. 76-77.

Documents

A sketch of the geology of the whitehaven district