Composition of surface layer bottom sediments from the Chukchi Sea

Abundance of noble metals and bulk chemical composition have been studied in bottom sediments of the Chukchi Sea. Distribution of noble metals and their correlation with major and trace elements in the sediments have been analyzed using multicomponent statistics. It was established that average contents of noble metals in the bottom sediments of the Chukchi Sea significantly exceed those both in shelf terrigenous sediments and stratisphere. Osmium and iridium enrich mixed and pelitic sediments relative to shallow-water sediments and their influx is presumably determined by erosion of coastal and bottom unconsolidated deposits. High Ag, Ru, Au, and Pt contents were identified in clayey sediments enriched in biogenic elements in the some areas of the Southern Chukchi plain (Chukchi Sea) confined to intersection zones of submeridional and sublatitudinal structures of the graben-rift system, which formed in Mesozoic and activated in Late Cenozoic.针对楚科奇海（Chukchi Sea）海底沉积物中的贵金属丰度及全量化学组成开展了系统研究。采用多分量统计方法，分析了沉积物中贵金属的分布特征及其与常量元素、微量元素的相关关系。研究证实，楚科奇海海底沉积物中贵金属的平均含量显著高于陆架陆源沉积物及地壳层中的对应水平。相较于浅水沉积物，混合沉积物与泥质沉积物中富集锇（Osmium）与铱（Iridium），其输入来源推测为沿海及海底未固结沉积物的侵蚀作用。楚科奇海南平原的部分区域位于中生代形成、晚新生代活化的地堑-裂谷体系（graben-rift system）的近经向与近纬向构造交汇带内，该区域内富集生源元素的黏土质沉积物中检测到较高含量的银（Ag）、钌（Ru）、金（Au）及铂（Pt）。