1996-97 - Birbal Sahni Institute of Palaeobotany

1996-97
south India. Documentation of frequency distribution of Neocomian dinoflagellate
cyst types from subsurface sequence of Palar Basin is being carried out.
Programme 4.3 Neogene calcareous nannoplankton palaeoceanography
of Andaman and Nicobar Islands
S.A. Jafar
Calcareous nannofossil data of Neogene sections exposed in various islands of
Archipelago group and Car Nicobar group was compiled using computer graphics.
Sawai Bay, Passa Bridge and Mus Jetty sections of Car Nicobar Island were studied
and calcareous nannofossil documentation was done under LM. Miocene/Pliocene
Boundary could be established in Sawai Bay section based on LAD of Discoaster
quiflqueramus, Triquetrorhabdulus rugosus and FAD of Ceratolithus acLltus.
Visited Car Nicobar, Kamorta and Great Nicobar Islands in Andaman sea region
and collected samples for palynological and nannofossil studies.
Programme 4.4 : Late Cenozoic diatom biostratigraphy of Andaman and
Nicobar Islands
Ani! Chandra
Rock samples from three sections namely Passa Bridge, Sawai Bay and Kakana
of Car Nicobar were chemically analysed for siliceous microfossils. Sawai Bay
Formation is exposed in all the three sections, whereas Kakana Formation is seen only
in Sawai Bay and Kakana sections. Samples from Sawai Bay Formation of Sawai Bay
section have yielded diatoms and silicoflagellates. The diatom assemblage from Sawai
Bay Formation indicates a Miocene-Pliocene age for this formation.
EDAX of selected rock chips from Car Nicobar was carried out. Consideration
was made to select the specimens from different stratigraphical horizons. Microfossils
having circular and bilateral symmetry were grouped separately. Composition of
siliceous microfossils in I sq mm of the slide was also determined. SEM photographs
and EDAX print-outs were prepared. XRD analysis of a few samples from Car Nicobar
was carried out through XDAL-3000 programme. A draft manuscript on the diatoms
from Car Nicobar is under preparation. A manuscript dealing with the lithostratigraphy
of Car Nicobar was finalized.
Visited Neill and Havelock islands to collect rock samples from Neogene
sequences (covering five sections) for diatom study. John Lawrence, Wilson, Strait and
Nicolson islands were also surveyed.
Programme 4.5 : Palaeogene-Neogene phytoplankton biostratigraphy and
palaeoceanographic set-up of Kutch and Saurashtra Basins,
India
K.P. Jain,
Rahul Garg & Khowaja-Ateequzzaman
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