1996-97 - Birbal Sahni Institute of Palaeobotany

1996-97
A total of 90 samples were processed, of which 64 samples were dated. Some
of the results are as follows:
Sediment samples from Sat-Tal, Dharali and one sediment sample from Chharka
Tal, Uttar Kashi (U.P.) have been dated to understand the depositional environment
and climate during the Quaternary Period in Himalaya. The base of Dharali sediments
was dated as 1240 ± 90 yrs BP. The C-14 date of Chharka Tal sediment at 3.65-3.75 m
depth comes out to be 2090 ± 140 yrs BP.
Two peat samples from Konalur River Basin, Kodaikanal have been dated to
work out the history of vegetation and climate in tropical montane forest in south
India. The C-14 date at base (140-150 cm) is 3360 ± 110 yrs BP. Peat samples from
Wadda Lake, Pithoragarh have also been dated and the rate of sedimentation works out
to 34 cm!1 000 yrs. Two peat samples from Paradise Lake, Selapass, Kameng, Arunachal
Pradesh have been dated to understand climatic change in the eastern Himalayan region.
The C-14 date at 1.0 m is 1650 ± 140 yrs BP.
Three charcoal samples from Raja-Nal-Ka-Tila near Ram Garh (U.P.) have
been dated to reconstruct regional models of agriculture and economic exploitation of
plants in the prehistoric past for the Vindhyan plateau region. At the depth of 3.15-3.2
m, C-14 date is 2830 ± 100 yrs BP.
Installation of Ultra Low Background Liquid Scintillation Counter is being
carried out. Fabrication of high vacuum system for synthesizing low volume Benzene
samples has been done and some trial syntheses of low volume Benzene samples have
been started. Microwave samples preparation system using microwave digestion method
for chemical analysis has been installed. Atomic absorption spectrometer has also been
installed and test measurements have commenced.
Thirty-nine samples have been dated as a part of consultancy services offered
by the Institute.
G. Rajagopalan & B. Sekar
Interpreted the past climatic changes around Tsokar Lake, Ladakh; Didwana
Lake, Rajasthan and Paradip River delta core on the basis of elemental analysis,
authigenic phosphorus concentrations. The results were presented in the IGBP
Symposium held at Bhubaneshwar.
Visited Kalpi and adjoining areas and collected shell and kankar samples for
I4C dating of Quaternary history of Gangetic alluvium.
Programme 8.3 : Potassium-Argon dating of sedimentary and igneous
rocks
C.M.
Nautiyal
A set of new Saes getters was fixed. The gettering action of the Ti-Zr as well as
Saes getters was monitored with temperature variation. Six thin sections of trap
specimens and four of the fossil wood were made. Modification in the MS control unit
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