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根据粒度、微体生物组合、矿物组分和微量元素丰度，探讨了南极布兰斯菲尔德海峡中央海槽和南部下陆坡区冰－海沉积环境形成的硅质沉积物特征。硅质沉积物主要为硅藻软泥或粉砂质硅藻软泥，由微体生物遗体、粘土矿物、火山物质和陆源碎屑矿物所组成。硅质生物壳体主要为硅藻，含量＞３０％，含少量放射虫和硅质壳有孔虫。粘土矿物中蒙脱石的含量高达５２．５％，其次为陆源伊利石，高岭石和绿泥石含量相对较低。碎屑重矿物以橄榄石、辉石、角闪石等非稳定组合为特征，轻矿物主要包括石英、长石和火山玻璃。微量元素丰度特征与大洋现代表层沉积物有所区别。研究区硅质沉积作用具有多种物源、生物沉积作用居重要地位、陆源（包括火山）物质以粉砂和粘土级细质点为主、相对较高的沉积速率和受地质构造背景影响等特征。
According to the grain size, microbial assemblage, mineral composition and trace element abundance, the characteristics of siliceous sediments formed in the ice-sea sedimentary environment in the central trough of the Bransfield Strait and the southern lower slope of the Antarctic are discussed. Siliceous sediments are mainly diatomaceous slime or silty diatomaceous slime, which consists of microbial remains, clay minerals, volcanic material and terrigenous detrital minerals. Silicate biological shell is mainly diatoms, content> 30%, with a small amount of radioactive insects and siliceous shell foraminifera. The content of montmorillonite in clay minerals is as high as 52.5%, followed by that of terrigenous illite, kaolinite and chlorite. Debris heavy minerals are characterized by unstable assemblages of olivine, pyroxene, hornblende, etc. Light minerals include quartz, feldspar and volcanic glass. The characteristics of trace element abundance are different from the modern ocean surface sediments. Silica deposition in the study area has many provenances and biologic sedimentation plays an important role. The terrigenous (including volcanic) sediments are dominated by silt and clay-like fine-grained sedimentary rocks and influenced by the geological structure .