1995-96 - Birbal Sahni Institute of Palaeobotany

BSIP
Palynological analysis of 250 m deep Sadanandpur profile, dating back to 160
ka yrs B. P., has been completed. It is the first attempt to present the palaeorecords of marine
palynology of the complete Quaternary sediments from Mahanadi delta in Orissa. Pollen
diagrams one each in curve and bar have been prepared. The whole pollen diagram has
been classified into 12 pollen zones and 6 barren zones in view to cxpress the finer
biostratigraphic units and to demarcate significant epochs and events since the time of
deposition of these sediments The pollen evidence has revealed several cyclic changes in thc
marine transgressive and regressive facies which are recorded between depth of236-250 m,
218-223 m and 170-211 m and the sea marginal conditions are recorded at the depth of 53­
142 m. The sanlples between the depths mentioned above have rcvealcd the preponderance
of core-mangrove taxa such as Rhizophora, Ceriops, Bruguiera, Xylocarpus, Aegialitis
rotundifolia, Excoecaria agaljocha, Avicennia, Sonneratia, Heritiera, etc. indicating the
marine facies with constant depths of sea-water. However, the samples between 48-50 m
depth have recorded fresh/brackish water pollen suggesting marine regression resulting into
the development of salt marshes. The age for the above events are extrapolated to 160 ka,
140 ka, and 90 ka, rcspectively. On the basis of litho- and palynostratigraphy, the ancient
shore lines have been suggested across the De1ang-Jagatsingharpur-Balasore.
The pollen diagrams of Chandrapur and Geokhala profiles (3.0 m each in depth)
havc been prepared through the TILIA computer software. Four photoplates have been
prepared for recovered palynodata from the aforesaid profiles.
S.P. II Palaeogene floral
palaeoenvironmental
93)
H.P. Gupta & Deepak Kohli
diversity-biostratigraphy
and
implications (DST NO. ES/441037/
Objeclives To document the palynological changes during Palaeogene
To decipher the extinction and evolutionary pattern of the
different palynotaxa
To infer the palaeoecological condition of deposition
A number of bore-hole corcs supplied by the MECL and GSI from the various
localities of Bikaner District, Rajasthan were chemically processed. A rich palynological
assemblage comprising mostly pteridophytic spores and angiospennic pollen was recovered.
The dominant species are Dandotiaspora dilala, Lycopodiumsporites specioslls,
Spinizonocolpites echinatus, Piladiporocolpiles caratinii, Tricolpites reticll/atus,
neocouperipol/is kutchensis, Retidiporoco/pites excel/emus, Proxapertites operculatus,
Ocimumpollenites indicus, etc. Besides, 13 bore-hole core samples drilled by the DGM,
Gujarat in Surat and Bhavnagar districts were also macerated. Out of 220 samples, 78
samples were productive and the slides of these samples were prepared.
R.K. Kar, Poonam Sharma & Reema Singh
S.P. III Reconstruction of past climatic changes in eastern Himalayan
region using tree-ring data (DST No. ES/44/018/90)
128