黄河口外沉积物氧化还原环境的表征

The Expression of Redox Environments in Sediments Outside of the Yellow River Estuary

为了评价黄河口外石油开发区沉积物的氧化还原特征,本文根据2002年9月航次所取得的黄河口外41个柱状沉积物样品,研究了该区沉积物氧化还原特征参数Fe3+,Fe2+ Fe3+/Fe2+及Eh,Es和有机碳、氧化还原度(ROD)等的分布特征,以及这些参数之间的相关关系.研究表明,Fe3+,Fe2+,Fe3+/Fe2+及Eh,Es和有机碳、氧化还原度(ROD)等在表层沉积物中各站之间的差别不大.Fe3+和Fe-在0～40 cm深度范围内变化比较复杂,40 cm以后变的相对比较稳定.而Eh和Es有随深度减小的趋势,ROD在整个研究区都小于1,有机碳的含量高于整个渤海的平均值.综合所有氧化还原特征参数的特征,可确认该区沉积物的氧化还原环境为还原性,该还原性特征主要是由有机碳控制的,而活性铁的贡献不明显.

In order to access the redox environments of near-sea petroleum development areas outside the Yellow river estuary, the distribution characteristics of Fe3+, Fe2+, Fe3+/Fe2+ ratio, Eh, Es, Corg, ROD and the relationship among them are discussed with 41 core samples obtained out of the Yellow River estuary in September 2002.The results show the horizontal distributions of Fe3+, Fe2+, Fe3+/Fe2+ ratio, Eh, Es, Corg, ROD have little difference in surface sediments. The variations of Fe3+, Fe2+ in the upper layer ( 0 ~ 40 cm ) are very complicated,but their contents become stable down below the depth of 40 cm. Eh and Es decrease with depth. ROD is less than 0 over the region. The content of organic carbon is higher than the average of the Bohai Sea. The redox environments belong to reduction according to all parameters. Organic carbon controls the character, and the contributions of active iron are less in this region.