标题：New interpretation for the main sediment source of the rapidly deposited sediment drifts on the northern slope of the South China Sea
作者：Luan, Xiwu; Ran, Weimin; Wang, Kuo; Wei, Xinyuan; Shi, Yanfeng; Zhang, Hao
作者机构：[Luan, Xiwu; Ran, Weimin] China Geol Survey, Qingdao Inst Marine Geol, 62 Fuzhounan Rd, Qingdao 266071, Peoples R China.; [Luan, Xiwu; Ran, Weimin; 更多
通讯作者地址：[Luan, XW]China Geol Survey, Qingdao Inst Marine Geol, 62 Fuzhounan Rd, Qingdao 266071, Peoples R China.
来源：JOURNAL OF ASIAN EARTH SCIENCES
关键词：The Northern South China Sea Slope; Rapidly deposited sediment drifts;; Miocene drape formation; The Dongsha Uplift; Bottom current; Sedimentary; source
摘要：The slope of the northern South China Sea (SCS) is one of the world's most active areas of modem marine sedimentary processes. A rapidly deposited sediment drift (RDSD) was identified on the slope near Dongsha Island. The sources of this body have been studied and discussed by several authors, but no consensus has been achieved. Based on multi-channel seismic profiles interpretation and data analysis of long-term observation of bottom currents, we identified that although the amounts of sediments input from the Pearl and Hanjing Rivers, and from Kao-ping and Tseng-Wen Rivers are large, considering the current situation of northern SCS, none of the Pearl River, the Hanjiang River, the Kao-ping River and the Tseng-Wen River can maintain the deposition pattern of the northern SCS margin as the single source, especially to maintain the supper high sedimentation rate at the RDSD area. The Miocene drape formation (MDF) calmly draped over an unconformity after rifting stage resulting in a relatively constant thickness of about 2000 m throughout the overall northern SCS continental margin, and followed by a standard configuration of a clinoform, the Pliocene formation and another clinoform of about another 700 m in total thickness. Due to Dongsha uplift since 3 Ma, roughly 1/2 of MDF and the N-2 formation in the Dongsha area measures 150 km by 200 km were denudated resulting in an average annual denudation rate of 60 x 10(6)t/y. If these sediments were deposited on a slope region within an area measuring 100 km by 100 km, the sedimentation rate could reach 250 cm/ky. This is clearly an impressive new sediment source that has never been discussed before. Moreover, the RDSD is near the Dongsha Uplift and on the adjacent slope. We believe that this new sediment source should be the main contributor for the RDSD development.