G E O L O G I C A L S T R U C T U R E O F B I H A R

B A I I , P A P E R 3 , U N I T - 5

B Y D R B H AWA N A N I G A M ,

D E P T O F G E O G R A P H Y, A N C O L L E G E ,

PAT L I P U T R A U N I V E R S I T Y, PAT N A .

INTRODUCTION

GEOLOGICAL TIME SCALE

THE FORMATION OF BIHAR

• The structure of Bihar is different from itsneighbouring states and the formation tookplace at different times.

• It is closely related with the upheaval ofHimalayan Mountains.

• It consist of vast alluvial plain,

• small hilly region in the north west portionknown as Someshwar hills and

• the southern most portion is made ofKaimur range, in the district of Gaya,Nawada, Munger, and Banka closelyassociated with Chotanagpur region.

GEOLOGICAL DIVISION OF BIHAR

• Based on above discussion the state can

be broadly divided into

• 1) SOMESHWAER HILLY REGION

• 2) VAST ALLUVIAL PLAIN

• 3) SOUTHERN MOST HILLY REGION.

SOMESHWAR HILLY REGION• Located in NW part of the state and it consist

of hills and dun range.

• It is part of Indo-Gangetic plain.

• Geologist believes that it has origin from the Geosyncline of Himalayas. Later it was subsided due to overload of sediments deposited by river.

• During the second upliftment of Himalayan mountains it was developed as hilly area.

• This is the border area ; where peninsular India joined with northern Asia, therefore consist of depressions and ridges.

• This area has undergone massive down wrapping and leads to crustal instability in NW part of Bihar.

ALLUVIAL PLAIN AREA OF BIHAR.• It consist of North Bihar and South Bihar Plain. This

plain area has similar geological formation likethose of Indo-Gangetic plain.

• North Bihar Plain has alluvial deposition by perinealrivers coming from the Himalayas and has uniqueGeological Formation.

• The plain has distinctive sediments characterisedby kankar, nodules, calcareous beds, in the areasof E & W Champaran, Sitamarhi and Sheohar Districts;it also include clay and mud in Ganga and Gandakdistrict.

• South Bihar Plain has deposition from the riverscoming from Chotanagpur plain and Madhya Pradesh.The plain has Khadar deposition having olderalluvium which consist of clay and sand.

• The SE portion of Bihar has silica deposition fromChotanagpur region..

SOTHERN HILLY REGION• The southern part of Bihar are

geological formation of Complex

nature having bare rocks of early

geological period.

• This region include Kaimur hilly

region, the hills of Gaya, Navada ,

Nalanda, Kiul, Munger, and

Banka etc.

• The rock consist of sandstone,

quartzite, limestone, dolomite,

and shales.

• The hilly terrain of Gaya, Nalanda,

Nawada, etc. are the outliers of

Chotanagpur plateau.

REFERENCE

• Sinha V.P et.all – Bihar land, people and

economy.

• National digital library

• Google scholar.

• Thanks.