Journal of Geological Society of India (Online archive from Vol 1 to Vol 78)

U. Bhattacharyya ¹, B. P. Chatterjee ¹

Affiliations
1 Geological Survey of India, 4, Chowringhee Lane, Calcutta 700016, IN

Abstract

Recent discovery of two widely separated marine fossil bearing calcareous horizons within the supposed deltaic Tura Sandstone, from the southeastern part of Langrin and southern part of Balphakram-Pendengru coalfields, have brought to light several important aspects. The fossil assemblage comprising foraminifera and algae suggests prevalence of marine environment - during Lower Eocene (Laki). lnspite of minor discrepancies in the fossil content of these two localities, the stratigraphic position of these two marine incursions has been found to be time equivalent of the Umlatdoh limestone of Lower to Middle Eocene (Laki) age (the middle biosparite calcareous member of Palaeocene-Eocene Sylhet Limestone) when large scale marine transgression is known to have occurred in adjoining eastern part of Khasi Hills and Jaintia Hills.

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U. Bhattacharyya ¹, D. K. Ghosh ¹, Purnendu Sen ¹, R. Chakrabarti ¹

Affiliations
1 Precambrian Geology Division, Geological Survey of India, Eastern Region M.S.O. Building, 6th Floor, 'E' Block, DF Block, Sector - I, Salt Lake City, Calcutta - 700 064, IN

Abstract

Spinifex textured perditotic Komatiites from Dhipasai-Sonajuri area, Singhbhum (East) - Bihar are reported for the first time. Deformed pillows and polyhedral joints are also recorded in the ultramafics of the area.

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