Multiscale ocean dynamics control the sedimentary source-to-sink processes in the southwestern Okinawa Trough (East China Sea)

Abstract

The sedimentary source-to-sink processes remain under debate in the southwestern Okinawa Trough due to its complex oceanographic context. We employe a multidisciplinary approach combining marine sedimentology and physical oceanography to address the sedimentary source-to-sink processes. This study shows that the East China Sea shelf has been the provenance of the southwestern Okinawa Trough during the past 3000 a, judged from the detrital zircon U-Pb geochronology. Numerical simulations indicated that the bottom currents are the primary drivers that transport sediments from the East China Sea shelf continuously entering the southwestern Okinawa Trough. This study confirms that the source-to-sink system in the southwestern Okinawa Trough is controlled by multiscale ocean processes, and verifies that the sediments are mainly sourced from the East China Sea shelf in the past 3000 a. These arguments greatly improve our understanding on the sediment dispersal and have important implications on the climatic and oceanographic reconstructions.