Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5113129 | Quaternary International | 2017 | 13 Pages |
Abstract
The present study uses clay mineralogy to delineate a â¼17 ka record of palaeoenvironmental/palaeoclimatic changes in the recently uplifted palaeogulf of Arabian Sea i.e. Great Rann of Kachchh (GRK). Situated on continental margin of Indian subcontinent and flanked by Indus delta, the GRK basin has preserved continuous record of post glacial sedimentation. Clay mineral studies on two long cores (â¼60 m and 50 m long) show more abundance of physical weathering products (illite and chlorite) over the chemical weathering products (smectite and kaolinite). We show that the GRK sediments depict multiple sources of sediment input. Dominance of illite-chlorite suggests GRK received sediments dominantly from the Himalayan terrain with minor contribution from adjacent regions. We present the oldest clay mineralogical signature of an interval of intensified monsoon conditions during the late Pleistocene (â¼17.7-16.3 cal ka B.P.). Monsoon became stronger before â¼8.4 cal ka B.P., and whereas the mid Holocene weakening of monsoon occurred after â¼7 cal ka B.P. Despite the differences in source region and composition of clay mineral records from the GRK with northeastern and southeastern Arabian Sea, the sedimentation responded to major climatic shifts that have occurred since the LGM.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Geology
Authors
Nitesh N. Khonde, Deepak M. Maurya, Laxman S. Chamyal,