摘要
根据粘土矿物和粒度以及环境因子分析测试资料,对东海中部近海表层沉积粘土矿物含量、分布特征及影响因素进行了分析讨论。结果表明,研究区表层沉积物中粘土矿物组合为伊利石–绿泥石–高岭石–蒙皂石,四种粘土矿物平均含量为:伊利石67.40%,绿泥石17.75%,高岭石12.28%,蒙皂石2.57%。研究区高岭石分布非常有规律,从西北近岸向东南外海方向含量逐渐减小,而伊利石含量则总体呈增加趋势,绿泥石分布较为均匀。研究区蒙皂石含量低,高值区分布北部边缘。研究区粘土矿物含量和分布主要受控于水动力条件,与水体介质的盐度有较为明显的相关性。高岭石和伊利石的分布特征表明了该区域沉积物的扩散沉积方向。蒙皂石在研究区北部边缘的较高含量,指示了来自北部黄河的物质向南的影响范围。
Based on the measurements of clay minerals and particle size as well as some environmental factors, the content, distribution characteristics and influencing factors of clay minerals in the surface sediments on the central East China Sea offshore area were analysed and discussed. The results show that the clay mineral assemblage in the study area is illite-chlorite-kaolinite-semctite, with the average contents are 67.40% for illite, 17.75% for chlorite, 12.28% for kaolinite and 2.57% for semctite. The distribution of kaolinite in the study area is very regular, with the content gradually decreasing from the north-west near-shore to the south-east offshore area, while the content of illite shows an increasing trend in general in the same direction, and the distribution of chlorite is more uniform. Semcite content is low in the study area and high values are distributed in the northern part of the study area. The content and distribution of clay minerals in the study area are mainly controlled by hydrodynamic conditions, and there is an obvious correlation between clay minerals contents and the salinity of the water. The distribution characteristics of kaolinite and illite indicate the patterns of diffuse and deposition of sediments in this area, and the northern part of the study area with higher content of semctite maybe suggests the south boundary of the materials from the Yellow River in the north have ever reached.
