闽江口表层沉积物中0.125—0.250mm粒级重矿物的分布与组合特征

着重研究了闽江口表层沉积物中０．１２５－０．２５０ｍｍ粒级的重矿物。结果表明，重矿物计有３４种，平均重量含量为１．９２％，主要矿物为磁铁矿，绿帘石、赤铁矿、角闪石、钛铁矿、锆石、云母等。与０．０６３－０．１２５ｍｍ粒级相比，虽然重矿物的种类相同，但其平均含量却低得多，显示闽江口重矿物富集于极细砂粒级中。

Study on heavy minerals in surface sediments of Minjiang Estuary

Heavy minerals of 0. 125~0. 250mm in the surface sediments of the Minjiang Estuary are studied. Results show that there are total 34 kinds of heavy ndnerals, with an average content of 1.92%. The minerals mainly include magnetite, epidote, hemantite, amphibole,ilmenite, zircon and mica. These types are the same to those of size 0. 063~0. 125mm,however,the average content is much more lower, which reveals that heavy minerals in the Minjiang Estuary are concentrated in the sise grade of very fine sand. According to content and distribution features of the main minerals, the Minjiang Estuary is divided into 4 ndneral composition zones. In each zone the composition of heavy minerals is greatly affected by the hydraulic condition and sedimental environment. The types of heavy minerals also shows that fragmentary minerals in the Minjiang Estuary originate from the weathered and eroded bedrock of the Minjiang River drainage area.