The marine sediment archives of Himalayan erosion

Marine sediment archives provide invaluable records of continental erosion and dynamics, important for understanding both crustal deformation and climatic processes. Yet these archives are influenced by autogenic and allogenic processes. Rigorous interpretation of these records therefore requires unravelling of these various intertwined factors, and a good understanding of source-to-sink.

The Bengal Fan is the largest marine sedimentary fan in the world. It, and its smaller “sister” the Indus Fan, as well as the Nicobar Fan, archive the erosional history of the Himalayas, the largest mountain belt in the world. Various IODP, and previously DSDP expeditions have cored the fans, and the material extensively studied to elucidate the history of the fans’ hinterland tectonics, source to sink dispersal patterns, and climatic variations through time, with an emphasis on the response to the Asian monsoons. Yet unravelling the competing influences on the sediment archives in this tectonically active region is challenging.

In this talk I will provide an overview on the use of isotopic provenance studies to discuss aspects of the progress made in using the archives to determine Himalayan tectonics, as well as in deconvolving autogenic versus allogenic influences and in our understanding of source-to-sink.