Clay mineral distribution in surface sediments of the South China Sea and its significance for in sediment sources and transport

• Published in: Chinese journal of oceanology and limnology Vol. 28; no. 2; pp. 407 - 415
• Main Authors: Liu, Jianguo, Chen, Muhong, Chen, Zhong, Yan, Wen
• Format: Journal Article
• Language: English
• Published: Heidelberg SP Science Press 01-03-2010; Springer Nature B.V
• Subjects: Chemistry; Chlorite; Clay; Clay minerals; Continental shelves; Distribution; Earth and Environmental Science; Earth Sciences; Geochemistry; Grain size; Illite; Illites; Kaolinite; Marine; Mineralogy; Minerals; Oceanography; Rivers; Sediment; Sediment sources; Sediment transport; Sedimentary environments; Sediments; Smectites; Trend analysis; X-ray diffraction; 南中国海; 泥沙来源; 珠江口地区; 矿产分布; 粘土矿物分析; 蒙脱石含量; 表层沉积物; 运输路线; South China Sea; Taiwan; Asia, Mekong R; China, People's Rep., Zhu R; ISEW, Borneo, Kalimantan; ISEW, Philippines, Luzon I; ISEW, South China Sea, Sunda Shelf; China, People's Rep., Changjiang R; ISEW, China, People's Rep., Hainan Prov., Hainan I; ISEW, South China Sea, Nansha Trough; ISEW, Taiwan; South China Sea; clay minerals; sediment transport; sediment sources; surface sediments
• ISSN: 0254-4059; 2096-5508; 1993-5005; 2523-3521
• DOI: 10.1007/s00343-010-9057-7

Clay minerals of surface sediments in the South China Sea （SCS） are analyzed with X-ray diffraction, and their transport is explored with a grain size trend analysis （GSTA） model. Results show that clay mineral types in various sedimentary environments have different sediment sources and transport routes. Sediments in the northern SCS （north of 20°N） between the southwest of Taiwan Island and the outer mouth of the Pearl River have high contents of illite and chlorite, which are derived mainly from sediments on Taiwan Island and/or the Yangtze River. Sediments from the Pearl River are characterized by high kaolinite and low smectite content, and most are distributed in the area between the mouth of the Pearl River and northeast of Hainan Island and transported vertically from the continental shelf to the slope. Characterized by high illite content, sediments from Kalimantan Island are transported toward the Nansha Trough. Sediments from Luzon Island are related with volcanic materials, and are transported westwards according to smectite distribution. On the Sunda Shelf, sediments from the Mekong River are transported southeast in the north while sediments from the Indonesian islands are transported northward in the south. Ascertaining surface sediment sources and their transport routes will not only improve understanding of modem transportation and depositional processes, but also aid paleoenvironmental and paleoclimatic analysis of the SCS.