Department of
Earth and Climate Science

Gyana obtained his PhD in Isotope geochemistry in 2011 from Physical Research Laboratory, Ahmedabad. He was a Post-Doctoral Fellow at Colorado State University, USA and worked at the National Institute of Technology, Rourkela before joining IISER Pune in December 2014.

Research

Low-temperature isotope geochemistry: Implications to chemical weathering and climate interaction

Gyana’s research mainly focuses on understanding and quantifying low-temperature aquatic processes, which include (i) Chemical weathering rates of the Himalayan river basins and its impact on global atmospheric CO2 budget, (ii) temporal changes in erosion pattern due to climatic changes, and (iii) Re-Os geochronology of organic-rich marine sediments. 

Some of his recent research findings are listed below: 

High-resolution oxygen isotopic study of a speleothem from core monsoon region reveals occurrence of a super-drought around 6.5 kyr B.P. This event was driven by warming of eastern Indian Ocean during this period.

Chemical study of a sediment core from the Arabian Sea show intensification of chemical weathering since 1,600 yr BP due to human-induced rise in C4 vegetation.

Detailed spatial and seasonal investigation of trace elements and their isotopes in a large tropical lagoon system (Chilika lagoon, India) show adsorptive boron removal onto clay surfaces. This led us propose that exchangeable boron in clay fractions can be efficiently used for reliable paleo-pH reconstruction.

Chemical weathering intensity in the Brahmaputra basin show minimal seasonal variation and is dominantly regulated by regional rapid weathering around the eastern syntaxis.

Selected Publications

Danish, M., Tripathy, G. R., Rahaman, W. (2020) Submarine groundwater discharge to a tropical coastal lagoon (Chilika Lagoon, India): An estimation using Sr isotopes. Marine Chemistry, 224: 103816, 1-13.

Samanta, A., Tripathy, G. R., Das, R. (2019) Temporal variations in water chemistry of the (lower) Brahmaputra River: Implications to seasonality in mineral weathering. Geochemistry Geophysics Geosystem, 20: 2769-2785.

Tripathy, G.R., Hannah, J., Stein, H., Geboy, N. and Ruppert, L. (2015) Radiometric dating of marine-influenced coal using Re-Os geochronology. Earth and Planetary Science Letters 432: 13-23.

Tripathy, G.R. and Singh S.K. (2015) Re-Os depositional age for black shales from the Kaimur Group, Upper Vindhyan, India. Chemical Geology 413: 63-72.

Tripathy, G.R., Singh, S.K., Ramaswamy, V. (2014). Major and trace element geochemistry of Bay of Bengal sediments: Implications to provenances and their controlling factors. Palaeogeography, Palaeoclimatology, Palaeoecology, 397, 20-30.