[M-IS16] Drilling Earth Science

[MIS16-P01] Drilling in the Bay of Bengal for reconstruction of the Indian summer monsoon variability

*Masanobu Yamamoto¹, Yoichi Usui², Uramoto Go-Ichiro², Takuto Ando³, Steven Clemens⁴, Kuhnt Wolfgang⁵, Leah LeVay⁶, IODP Exp 353 Scientists (1.Faculty of Environmental Earth Science, Hokkaido University, 2.JAMSTEC, 3.Graduate School of Science, Hokkaido University, 4.Brown University, 5.Christian-Albrechts-Universitat zu Kiel, 6.Texas A&M University)

Keywords:Bay of Bengal, IODP Exp. 353, Indian monsoon

The Indian summer monsoon brings rainfall in the Indian Subcontinent, and the precipitated water flows mainly into the Bay of Bengal. We can, thus, understand past changes in the Indian summer monsoon variability by estimating paleosalinity and riverine sediment load in the Bay of Bengal. During IODP Exp. 353 (iMonsoon; November 2014 to January 2015), we drilled six sites in the Bay of Bengal and the Andaman Sea. Cretaceous to Quaternary pelagic sediments were retrieved at Site U1443 (Ninetyeast Ridge). Miocene to Quaternary turbidites and hemipelagites were retrieved at Site U1444 (central Bay of Bengal). Miocene to Quaternary and Middle Pleistocene hemipelagic sediments were retrieved at Sites U1445 and U1446 (Mahanadi basin off India), respectively. Miocene to Quaternary hemipelagic sediments were retrieved at Sites U1447 and U1448 (the Andaman Sea).