The geochemical indicators, such as mineral, trace element and isotopic geochemistry and organic geochemistry indices, are of the most importance in the study of anoxicenvironment.
在缺氧环境的研究中，地球化学指标如矿物、微量元素、同位素和有机地球化学指标最为重要。
2
The black unit including a biotic extinction was caused by oceanic anoxic event. Crisis that deepwater keeled foraminifera encountered represents a ferocious anoxia in deep marine environment .