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根据1984年11月—1985年4月首次南大洋考察所取得的样品和资料，通过萃取液萃取并利用荧光素法测定不同形态硒，对硒在南大洋沉积物中的地球化学状态进行了研究。结果表明，西南大洋表层沉积物的总硒含量为278－1168×（10-9），其与粘土粒级有较密切的关系。硒含量的地理分布表现为海湾＞半深海＞外陆架；沉积物中硒含量不同，但其地球化学形态分配比基本相同，分别为可交换态占15％，有机结合态占36％，无机盐态占4％，晶质氧化物态占9％，矿物晶格态占37％；沉积物剖面中间隙水硒的含量变化与铁一致，在铁氧化物还原带达到峰值；可交换态硒的含量随深度的增加而升高，而晶质氧化物态的含量则随深度而降低；有机质的早期成岩分解是沉积硒参与再循环的主要来源；计算得出沉积柱表面逸入上覆海水的硒通量为3．5ng／（cm2·a），沉积通量为13．4ng／（cm2·a）。
According to the samples and data obtained from the first Southern Ocean Expedition from November 1984 to April 1985, the geochemical state of selenium in the sediments of the Southern Ocean was studied by extracting with extract and measuring the different forms of selenium by fluorescence method . The results show that the total selenium content in the surface sediments of the Southwest Ocean is 278-1168 × (10-9), which is closely related to the grain size of the clay. The distribution of selenium content is in the order of gulf> semi-deep sea> outer shelf. The selenium content in sediments is different, but its geochemical distribution is basically the same, accounting for 15% of exchangeables, 36% of organic bounds, State accounted for 4%, crystalline oxide state accounted for 9%, crystal lattice state accounted for 37%; sediment section in interstitial water selenium content changes consistent with iron, in the iron oxide reduction zone peak; exchangeable selenium The content of crystalline oxide increased with depth while the content of crystalline oxide decreased with the depth. The early diagenesis of organic matter was the main source of selenium involved in recirculation. The sediment surface was evolved into the overlying seawater Selenium flux is 3.5ng / (cm2 · a) and deposition flux is 13.4ng / (cm2 · a).