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硫酸盐-甲烷界面在富甲烷和含天然气水合物的海洋沉积区已经成为一个重要的生物地球化学识别边界。在硫酸盐-甲烷界面之上,沉积物中的硫酸盐因参与分解有机质和甲烷厌氧氧化反应而被消耗,而界面之下沉积物中的甲烷则不断生成,含量逐渐增加。根据该界面附近硫酸盐浓度和甲烷浓度的变化特征,可以判断该区甲烷流体通量的大小,从而指示下伏天然气水合物的可能赋存状况。南海北部陆坡的柱状沉积物孔隙水数据的分析显示,其硫酸盐-甲烷界面埋深比较浅,表明该海域的甲烷通量较高。这种高甲烷通量很可能是由下伏的天然气水合物所引起的,并暗示着该区下伏海底可能有天然气水合物沉积层赋存。
Sulfate-methane interface has become an important biogeochemical boundary for recognition in marine deposits that are rich in methane and contain gas hydrates. Above the sulfate-methane interface, the sulfate in the sediments is consumed due to the anaerobic oxidation of decomposition organic matter and methane, and the methane in the sediments below the interface is continuously increased and gradually increased. According to the change of sulfate concentration and methane concentration in the vicinity of the interface, the flux of methane fluid in this area can be judged, indicating the possible occurrence of gas hydrate in the next. Analysis of pore water data from columnar sediments in the northern South China Sea shows that the depth of the sulfate-methane interface is relatively shallow, indicating a high methane flux in this area. This high methane flux is most likely caused by the underlying gas hydrate and suggests that gas hydrate deposits may occur beneath the seafloor in this area.