1995-96 - Birbal Sahni Institute of Palaeobotany

1995-96
PROJECT I
Research
Projects and Programmes
ANTIQUITY, RADIATION AND EVOLUTIONARY
TERNS OF EARLY LIFE
PAT­
Programme
Ohjective
I. I
Palaeobiology of Vindhyan Basin
To identify metaphytes and metazoan hody ji-Jssils,
ichnofossils and their relics from the Proterozoic succession
and their evolution and diversification
To identify organa-sedimentary stmctures found in association
of metaphytes and metazoans and to decipher
environmental conditions
To determine the significance of metaphytes and
metazoans in hiostratigraphy
Macroscopic biota comprising Chuaria - Tawuia - Krishnania were studied from
the argillaceous sediments of Rohtas Formation, in Bihar, Uttar Pradesh and Madhya
Pradesh. The sediments represent topmost part of the Semri Group. Two distinct
carbonaceous impressions were identified, both belonging to the family Bryopsidaceae
(Chlorophyta). The feather-shaped fomls compare morphologically to Bryopsis and
branched filamentous fonus bearing lateral spheroidal stmctures to Derhesia. This
evidence supports the presence of Chlorophyta even during ± 1000 Ma years before.
New collection was done from the Lower Bhander Limestone Formation exposed
around Bainkuiyan, Madhya Pradesh. Another problematic trace fossil showing fine
curvature was marked. Additionally a macroscopic foml Sekwia Hofmann (reported
from the Vendian of Canada) was recorded. The presence of Sekwia was previously not
known from the Indian Precambrian. Examined tubular forms of ichnofossils previously
described from the Kaimur. The septate tubular form indicates that it may be representing
resting stage of metazoan.
Studied 30 samples exposed around Judwani area, Semri Group of Madhya Pradesh
both in thin section and maceration. The acritarch and cyanophycean forms arc poorly
preserved and highly distorted.
P.K. Maithy & Rupendra Babu
Programme 1.2 Palaeobiology ofthe Proterozoic sediments in Cuddapah,
Kaladgi and Bhima basins
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