Sedimentary characteristics and processes revealed by the push cores of the 140^th dive of DSV "Jiaolong" in the Taiwan Submarine Canyon, Northern South China Sea

Transportation and deposition of sediments in submarine canyons are critical for understanding the deep-sea processes and environments, particularly the turbidity currents. In this paper, three push cores, collected from three sites in the middle reaches of the Taiwan Submarine Canyon during the 140^th dive of Chinese DSV (Deep Submersible Vehicle) "Jiao Long", are analyzed for sediment characteristics, sources, and depositional processes. The upper parts of the push cores are dominated by homogeneous fine-grained sediments signified by a typical hemipelagic-pelagic benthic foraminifera assemblage. In contrast, the lower parts consist of coarse-grained sediments and assemblages of "shallow-water" benthic foraminifera typically occur in coastal or shelf areas. Their depositional characteristics suggest a down-slope transportation most likely by turbidity currents along the canyon. AMS¹⁴C dating indicates that the turbidite was formed approximately 150 cal.aBP, and the clay mineral compositions suggests a kind of hemipelagic-pelagic and the turbidite deposits with sediment sources dominantly from the Taiwan island and partly from the Pearl River and Luzon Island.