DHARWAR SUPER GROUP

CONTENTS:INTRODUCTION

DHARWAR CRATON -WDC AND EDC

BABABUDEN-WESTERN GHATS-SHIMOGA SUPER BELT

CHITRADURGA-GADAG SUPER BELTEDCCONCLUSIONREFERENCES

INTRODUCTION:-Tectonic division of indian shield

into five cratons thy areDharwar cratonSinghbhum cratonAravalli cratonBundelkhand cratonBastar craton

TECTONIC MAP OF INDIA

Craton:- a large tectonically stable

block of the earth's crust. Dharwar craton is divided into two tectonic blocks in the year 1986 by Rogers. Western Dharwar craton Eastern Dharwar craton These 2 cratons divided by the chitradurga

shear zone.The grey gneiss complex covering the

entire craton formerly known as peninsular gneiss.

DHARWAR CRATON:-

WDC EDC

SCHIST BELT LARGE WITHVOLCANICS, SUBORDINATE SEDIMENTS.

NARROW, WITH GREENSTONE BELTS. PILLOW BASALTS.

BASEMENT IS PENINSULAR GNEISS. UNCONFORMITY MARKED BY QPC.(<3000MY)

DHARWAR BATHOLITH INTRUSIVE ON ALL SIDES .(2500-2700 MY)

OLDER SEQUENCE (SARGUR GROUP)AS NARROW BELTS AND ENCLAVES, ABUNDANT IN THE SOUTH.

OLDER SEQUENCE(WARANGAL GROUP) MOSTLY AS ENCLAVES IN THE NORTH.

INTER MEDIATE PRESSURE METAMORPHISM.

LOW PRESSURE METAMORPHISM.

WDC:-IT OCCUPIED BY VAST AREAS OF PENINSULAR INDIA WITH 2 PROMINENT SUPER BELTS Bababudan-western ghats-shimogaChitradurga-gadag.It is belonging to dharwar super group.

BABABUDEN-WESTERN GHATS-SHIMOGA SUPER BELT: THIS SUPER BELT SPREAD AN AREA APPROX. 300 KM LONG AND 100-150KM WIDE. SCHISTOSE ROCKS OCCUPYING 30000KM SQ.REAMINING 15000KM SQ, OCCUPIED BY BASEMENT PENINSULAR GNEISS.Bababudan SCHIST BELT OCCUPIES AN AREA 2500 SQ, KM.A PROMINENT BUT THIN HORIZON OF QUARTZ PEBBL CONGLOMERATE .THIS GROUP IS DOMINENTLY MADE UP OF METABASALT WITH INTERBEDDDED CROSS-STATIFIED QUARZITES, CAPPED BY A PROMINENT BIF.AGE IS ABOUT 2700-2800MY.

CHITRADURGA-GADAG SUPER BELT:-

COMMONLY THIS BELT IS KNOWN AS CHITRADURGA SHIST BELT.COVER AN AREA IS ABOUT 400KM LONG.5KM WIDTH IN THE NORTH WITH BULGES OF ABOUT 25KM. THIS SCHIST BELT SIGNIFICANCE OF GOLD AND K-RICH GRANITOIDS. CONSIST OF PHYLLITE,LIMESTONE,MANGANESE FORMATOINS AND BIF.

EDC:-OLDER GNIESSES :age is about 3000my . Greenstone belts are

seen in kolar and ramagiri that of putative basement.

Warangal group:-significance difference is that this group

occurs to the east of eastern green stone belts ,whereas eastern margins of these individual green stone belts do not have QCP and therefore this group enclaves may be older .

Kolar group(CHITRADURGA GROUP )

Yaswantanagar formation(BABABUDAN GROUP )

CONCLUSIONS

Dharwar super group is exposed both in WDC and EDC.

Age is about 2600-2800MY.In WDC dharwar super group as

divided into chitradurga and bababudan group.

In EDC dharwar super group as divided into kolar and yashwantanagar formation.

References:Geology of India Volume1

by M. Ramakrishnan and R.Vaidyanandhan published by geological society of india , bangalore .2008.

Geology of India and burma.

by M.S. Krishnan. the madras law journal office.1949.

Geology of india by D.N. wadia.

www.geosocindia.com/abstracts/2009/jan/fullpapers/f5

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