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研究了南海东沙群岛附近海域表层沉积物中二类粒级（０．０６３～０．１２５ｍｍ和０．１２５～０．２５ｍｍ）的碎屑矿物。结果表明，碎屑矿物共有５２种，其中轻矿物１５种，重矿物３７种；前者平均含量为９８．８３％，后者仅为０．５２％。依据主要矿物的含量和分布特征，将该海域划分为三个矿物组合带．从海岸向陆架、陆坡，陆源碎屑逐渐减少，生物源物质不断增多；水深６７０～７４０ｍ的陆坡内褐铁矿含量较高，表明该区处于水体交换频繁的高能氧化环境．
The detrital minerals of the second type (0.063 ~ 0.125mm and 0.125 ~ 0.25mm) in the surface sediments near the Dongsha Islands in the South China Sea were studied. The results show that there are 52 kinds of detrital minerals, including 15 kinds of light minerals and 37 kinds of heavy minerals; the average content of the former is 98.83% and the latter is only 0.52%. According to the content and distribution of major minerals, the area is divided into three mineral assemblages. From the coast to the continental shelf, the continental slope and terrigenous detritus gradually decreased, and the biogenic materials increased continuously. The content of limonite in the slope of 670 ~ 740m was higher, indicating that the area was in a high-energy oxidation environment with frequent water exchange.