New frontiers in scientific drilling of the Indian Ocean

The Indian Ocean exerts a fundamental control on the Earth’s climate and hosts a variety of complex tectonic features. It influences the Indian Monsoon and hosts a major part of the thermohaline conveyor. It has been over a decade since scientific drilling occurred in the Indian Ocean, and as such there are major gaps in geoscientific understanding of this region. Future drilling of the sedimentary archives in the region will yield substantial information on the history of uplift, erosion, deposition and monsoonal history. It will improve our understanding of greenhouse/icehouse and ocean gateway dynamics and reef development. The region also hosts exceptional examples of Earth system processes and products that drilling will play an important role in illuminating. It would answer questions associated with subduction and tectonic plate breakup and reorganization. Major geodynamic issues to be investigated include hotspot/spreading ridge interactions and constraints on the mantle reference frame. There are many deep biosphere mysteries that may be solved by drilling sediment, such as the impact of Himalayan uplift and the monsoon on subseafloor community diversity. Drilling oceanic crust will reveal the nature of poorly known microbial communities at ridge systems, providing insights into the composition and abundance of microbial communities in different crustal provinces.