台湾海峡表层沉积物的粒度和碎屑矿物分布特征

摘要

Hierarchical clustering and factor analysis are respectively applied to the grain size composition of 283 surface sediment samples and the mineral analysis of 85 sediment samples collected in the Taiwanrn Strait. The results show that the surface sediments contain six kinds of sediment types in the Taiwan Strait, they can be divided into three types of depositional environment areas corresponding to sedimentary dynamics properties. Sixty-one kinds of minerals were found in the surface sediment samples, light minerals are main, with average content up to 97. 73%, 14 kinds of light minerals were found. The content of heavy minerals is low, with an average of 2. 27%,47 kinds of heavy minerals were found. The most important factor that influences the mineral distribution and content variation of the surface sediment in the Taiwan Strait is matter source, followed by hydrodynamic conditions and mineral own metamorphic degree, etc. The main matter source of the sediment in the Taiwan Strait includes the detrital matter from the rivers in Fujian Province and Taiwan Province, the erosion and denuded substances from both sides of the Taiwan Stait, Hanjiang River and parts from the Changjiang River and the Qiantang River substances carried by the Zhejiang and Fujian coastal current, the residue in the Taiwan Strait of late Pleistocene and some authigenic minerals,etc.%应用系统聚类分析和因子分析的方法对台湾海峡283个表层沉积物样品的粒度组成和85个样品的矿物组成进行了分析,结果表明:台湾海峡表层沉积物由6种沉积物类型组成,可以划分把它们为3种与沉积动力相对应的主要沉积环境区；在表层沉积物共发现碎屑矿物61种,以轻组分矿物为主,平均含量高达97.73％,共发现轻矿物14种；重组分矿物含量较低,平均为2.27％,共发现47种重矿物.影响台湾海峡表层沉积物矿物分布及含量变化的最重要因素是物质来源,其次是水动力条件以及矿物自身的变质程度等.台湾海峡表层沉积物的主要物质来源包括来自福建和台湾省河流的入海泥沙、海峡两岸的侵蚀和剥蚀物质、韩江及部分来自浙闽沿岸流携带的长江和钱塘江物质,台湾海峡晚更新世残留物及部分自生矿物等.