Kaoping River – Sea sediments from source to sink traced with clay mineralogy

Tuesday, 16 December 2014
Yangyang Wang1, Daidu Fan1, James T Liu2 and Yuan-Pin Chang3, (1)Tongji University, Shanghai, China, (2)NSYSU National Sun Yat-Sen University, Department of Oceanography, Kaohsiung, Taiwan, (3)NSYSU National Sun Yat-Sen University, Kaohsiung, Taiwan
River bed sediments were collected from the main stream and major tributaries of the Kaoping River in Taiwan for clay mineralogy study. Marine sediments from boreholes on the seafloor off Taiwan in the northeastern South China Sea were also examined for comparison. The results show that the clay mineral composition of the Kaoping River display a similar pattern through the whole truck steam, with illite being dominant, chlorite being lesser abundant, and very scare kaolinite and smectite. Clay mineralogy shows some differences, like Smectite only examined in Qishan lake, one of the upper tributaries, which corresponed to the heterogeneous source rocks. The illite crystallity and the illite chemical weathering index both show rapid mechanical denudation. Compared with the other famous rivers in the world, clay mineral composition of sediments is influenced by the source and weathering based on the different gradients and environment. The data from marine sediments does not show obvious basin-wide differences, reflecting a distinct character of Taiwan source.