01-05 December 2025
INCOIS, Hyderabad, India.
| Abstract Submission No. | ABS-03-0296 |
| Title of Abstract | Multiproxy reconstruction of Late Quaternary climatic variability from the sediments of the western Bay of Bengal |
| Authors | Nayana V Haridas*, Upasana S. Banerji, D. Padmalal, K. Maya, P. John Kurian, Ravi Bhushan, A. K. Sudheer |
| Organisation | National Centre for Earth Science Studies, Thiruvananthapuram |
| Address | National Centre for Earth Science Studies Thiruvananthapuram, Kerala, India Pincode: 695011 E-mail: nayanaharidas6@gmail.com |
| Country | India |
| Presentation | Oral |
| Abstract | The Bay of Bengal (BoB), is significantly influenced by climate variables and natural climate forcing mechanisms and receives precipitation from the Indian Summer Monsoon (ISM) and North East Monsoon (NEM). This coupled with the fluvial discharges of sediments and water from both Himalayan and peninsular rivers have a major stake on the geochemical processes of the nearby regions. Considering the unique geoenvironmental features of the BoB and its connections to global climate forcings, the present study aims to unravel the paleoclimate and paleoceanographic variability, using a chronologically dated 2.90m long sediment core retrieved from the western BoB. Sediment deposition occurred in a tranquil and low-energy setting, with a relatively slow sedimentation rate during 45⿿15 ka and last 8 ka, in contrast to 15⿿8 ka interval. The core site received organic carbon from both terrestrial C4 plants and marine sources, with a predominance of terrestrially sourced C4 plants during 45⿿15 ka. The multiproxy analysis indicated stronger ISM during 45⿿28 ka and 14⿿4 ka, interspersed with a period of weakened monsoon. Nonetheless, between 25⿿14 ka and the last 4 ka, there was an increase in calcareous productivity, which is attributed to a decrease in the ISM and poor fresh water stratification over the BoB. In contrast, the strengthened ISM during the period of 14⿿4 ka led to increased freshwater inflows, resulting in significant freshwater stratification in the western BoB, which subsequently hindered calcareous in-situ productivity. Based on the Principal Component Analysis, two dominant processes, i.e. terrigenous sediment input and oceanographic processes, had a strong bearing on the geochemical variability at the core location. The provenance of sediments was prominently from the Deccan basaltic and the Archean crystalline rocks in the hinterlands. This study underlines that the millennial-scale hydroclimate changes in the BoB are significantly linked with the regional and global climate dynamics. |
| Are you part of IIOE-2 endorsed project | no |
| Keywords | Sediment, Indian Summer Monsoon, Bay of Bengal, Paleoclimate, Productivity |
| For Awards | no |