A DATA DRIVEN APPROACH TOWARDS COMPREHENSIVE UNDERSTANDING OF THE BAY OF BENGAL’S EVOLUTION FROM ITS BIRTH TO PRESENT FORM

The Bay of Bengal (BOB), the largest submarine fan system on the Earth resting mostly on Gondwanan (Cretaceous) oceanic basement, consists mainly of the Ganges/Brahmaputra/Meghna Delta system derivatives. BOB is continuously accommodating a vast amount of sediment load derived from the Himalayan mountain systems. BOB’s sediment thickness vary from a few kilometers to more than few tens of kilometers and its evolutionary history started way back in time during the late Mesozoic (Jurassic/Cretaceous), with the breakup of Gondwanaland, as greater India separated from Antarctica and drifted to the north, presumably controlled by the late Quaternary geologic changes in the fluvio-dynamic processes, eustatic sea-level changes, climatic changes and tectonic activities.

The BOB basin is characterized by clear blue tropical water with seasonal cycles of color, monsoon induced changes in physical and chemical properties of the water and its circulation, submarine canyons, littoral sand drifts, negative gravity anomalies between the continental region of peninsular India and the 90E ridge, proximity of 85E ridge hot spot activity juxtaposed with down-faulted continental blocks buried under enormous thick piles of sediments.

BOB's complex evolution to the present form needs a comprehensive review for better understanding connecting all related aspects. In this project, the authors attempt to acquire drilling data from Deep Sea Drilling Project (DSDP), International Ocean Discovery Program (IODP), and other cores drilled by various Indian agencies, which are not included and examined comprehensively. It is believed reviewing diverse drilling data along with tectonic, lithologic, magmatic and climatic signatures will be positive toward the comprehensive understanding of the evolution of the BOB. The datasets to be reviewed include but not limited to total sediment thickness (NGDC), relationship between the observed and/or model sediments and the age of the ocean crust or the presence of 85°/90° E ridge, and negative gravity anomalies, terrigenous vs. chemical/biochemical sediment interplay along with the onset of SW monsoon, salinity and productivity patterns, increased freshwater and nutrient input from rivers, geophysical data including basin dynamics and investigating Mesozoic tectonics.