南海北部陆架海域表层沉积物黏土矿物分布特征及物源分析

应用X射线衍射(XRD)对南海北部陆架海域225个站位表层沉积物黏土组分进行分析,结果表明,研究区黏土矿物总体以伊利石和绿泥石为主,高岭石和蒙脱石质量分数少,绿泥石、高岭石与蒙脱石质量分数呈明显的负相关关系。根据南海北部陆架海域表层沉积物中黏土矿物空间分布特征,结合邻近河流的黏土矿物组分以及洋流搬运作用,雷州半岛东部海域伊利石主要来源于广东沿海河流和珠江,绿泥石来自台湾岛,蒙脱石主要由吕宋河流提供,高岭石则由广东沿海河流和海南岛入海河流提供;雷州半岛西部海域伊利石来源于珠江,绿泥石和高岭石由红河提供,蒙脱石可能受广西入海河流携带的沉积物影响。

Distribution characteristics and source analysis of clay minerals in the surface sediments from the shelf of the northern South China Sea

X-ray diffraction (XRD) is used to analyze the clay composition of surface sediments from 225 stations from the continental shelf of northern South China Sea. The result shows that the dominant clay type is illite and chlorite, accompanied with minor kaolinite and smectite. The content of chlorite and kaolinite displays distinctly negative relationship with that of smectite. Combining the distribution pattern of clay minerals of this area with clay mineral composition of nearby river and ocean current, it is concluded that the illite in eastern waters of the Leizhou Peninsula is mainly derived from Pearl River and coastal rivers in Guangdong Province, the chlorite from Taiwan island, the smectite from Luzon River and the kaolinite is mainly transported by the coastal rivers in Guangdong and seagoing rivers in Hainan province. Illite in the western waters of the Leizhou Peninsula is from Pearl River, the chlorite and the kaolinite are from Red River and the smectite is probably affected by the sediments carried by seagoing rivers in Guangxi Province.