TIMANIAN OROGENYAND

LATE NEOPROTEROZOIC SUBDUCTION

V. PEASE, STOCKHOLM UNIVERSITY

EXTENT OF TIMANIAN OROGENY

Sediment cover (undifferentiated)

Paleozoic orogens

Timanian age complexes

Precambrian crystalline basement

Rift basins

500 km

Black Sea

N65°

E10° E20° E30° E40° E50° E60°

N55°

N45°

East Eur opean Cra ton

BalticSea

Pericaspian Basin

PEASE et al., IN PRESS

Caledonides

500 km

Caspian Sea

Black Sea

Donets basin

Pericaspian Basin

East Eur opean Craton

GEOMETRY OF TIMANIAN OROGENY

10 cm 1 m

10 cm 10 mm

FORELAND BASIN

1 km

2

3

4

0 100 200 300 400 500 600 km

cratonbasement

basalt Late Paleozoicsediments

SW NETIMAN RANGEMEZEN BASIN

555 Ma

Late Neoproterozoic

Early & MiddleNeoproterozoic

GRAZDANKIN, 2004; MARTIN et al., 2000

FORELAND BASIN

TIMAN RANGE FOLD & THRUST BELT

LORENTZ et al., 2004

SW NE

Mesozoic

Quaternary Quaternary

Paleozoic

overlying units (not exposed)

Tabuyevskaya Group

Tarkhanovskaya Group

Mikulkinshaya Groupand underlying Neoproterozoic units

Neoproterozoic pericratonic sedimentsof BalticaN

eoproterozoic

FORELAND FOLD & THRUST BELT

LORENTZ et al., 2004

TIMAN RANGEREGIONAL

METAMORPHISMgr+bt+mu+pl+k-spar+q ky st

gr-bt thermometerGASP barometer

+ +

0400 500

T (°C)

andalusite

sillimanite

kyanite

Bohlen et al., 1991

600 700 800

0.2

0.4P (GPa)

0.6

0.8

1.0

0400 500

T (°C)

andalusite

sillimanite

kyanite

Bohlen et al., 1991

600 700 800

0.2

0.4P (GPa)

0.6

0.8

1.0

0400 500

T (°C)

andalusite

sillimanite

kyanite

Bohlen et al., 1991

600 700 800

0.2

0.4P (GPa)

0.6

0.8

1.0

LORENTZ et al., 2004

TIMANPECHORAREGION

VENDIAN ACCRETEDTERRANES/URALIANFORELAND ANTICLINES

BOLSHEZEMEL ZONE

URALIAN OCEANICCRUST & VENDIAN BASEMENT

PECHORA ZONE

IZHMA ZONE

1

5

47

8

2

3

44°E 52°E 60°E

66°N

65°N

63°N

WESTSIBERIANBASIN

Barents Sea

Kara Sea

POLA

R U

RALS

S YKTYVKAR

KaninPeninsula

UKHTA

TIMAN R

ANGE

INTA

VORKUTA

100 kmgranitoidsediment & gneiss

A

B

1-Dinyu1-Novaya 1-Ronayol 1-West Dutovo1-Malole-bedinskaya

2-CharkayuLunvozh

1-NorthSavinobor

Paleozoic&

younger

Paleozoic&

younger

Paleozoic&

younger

Paleozoic&

younger

Paleozoic&

younger

Paleozoic&

younger

Paleozoic&

younger

4045 m

7

4766 m(bottom)

4230 m

9

2

8

diorite (565 Ma)

5

4501 m(bottom)

4240 m4

4303 m(bottom)

3600 m

4

3900 m(bottom)

3500 m

1, 63800 m(bottom)

3005 m

3

3208 m(bottom)

4844 m

10

4900 m(bottom)

gabbro, dolerite, or diorite

granodiorite

meta-andesite orandesitic tuffsmeta-basalt orbaslatic tuffs

vertical scale

unconformityfracture

40 m

PECHORA ZONE MAFIC COMPLEX

b.

a.

270°

70°130°

NeoproterozoicEnganepe Complex

Cambro-Ordoviciansediments

HINTERLAND

REGIONAL UNCONFORMITY & RETURN TO PASSIVE MARGIN

• AGE OF OVERLYING SEDIMENTS <500 Ma (PEASE, UNPUBLISHED DATA)

• AGE OF NEOPROTEROZOIC OPHIOLITES ca. 670 Ma (KHAIN ET AL, 1999)

KVARKUSH BLUESCHIST

BECKHOLMEN & GLODNY, 2005

•350-400 °C•7-8 Kilobars

•540 Ma

TIMANPECHORAREGION

VENDIAN ACCRETEDTERRANES/URALIANFORELAND ANTICLINES

BOLSHEZEMEL ZONE

URALIAN OCEANICCRUST & VENDIAN BASEMENT

PECHORA ZONE

IZHMA ZONE

1

5

47

8

2

3

44°E 52°E 60°E

66°N

65°N

63°N

WESTSIBERIANBASIN

Barents Sea

Kara Sea

POLA

R U

RALS

S YKTYVKAR

KaninPeninsula

UKHTA

TIMAN R

ANGE

INTA

VORKUTA

100 kmgranitoidsediment & gneiss

A

B

SCHEMATIC PECHORA X-SECTION

TIMANIAN OROGENESIS

ONSET? ±600 Ma

PEAK METAMORPHISM? ±550 Ma (REGIONAL P/T 600°C, 25-28 KM)

STRUCTURAL STYLE? NW-STRIKING, SW-THRUSTING, OCEAN/ARC- CONTINENT COLLISION

END? 500 Ma

TECTONIC RECONSTRUCTIONS

Greenland

Iceland

Baffin is.

Alaska

Russia

SVALBARD

FranzJosefLand

NOVAYA

ZEM

LYA

SEVERNAYAZEMLYA

180°

90°E90°W

TAIMYR

Kara Sea

Barents Sea

SeaLaptev

East Siberian Sea

Chukchi Sea

POLARURALS

LOM

ONOSO

V RID

GE

2000

3500

2000

0°

3500

v

v

v

v

EURASIANBASIN

CT

NT

PECHORA

BASIN

REGIONAL OVERVIEW

CRITERIA FOR SUBDUCTION TECTONICS

STERN, 2005

•OPHIOLITES•BLUESCHISTS•UHP METAMORPHISM

NO SMOKING GUN, BUT…..

THE NEOPROTEROZOIC TIMANIDE OROGEN

OF EASTERN BALTICA

eds. GEE & PEASEGEOL. SOC.

LONDON MEMOIR 30, 2004

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