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海洋水合物以其潜在的巨大资源价值和环境效应近年来引起地学界的极大关注,南海北部陆坡是我国重点研究的海域之一。ODP184航次在南海北部实施的钻孔为该区水合物研究提供了宝贵的第一手资料。通过对钻孔资料的研究表明,东沙东侧沉积速率比西侧高得多,对水合物的形成更有利。1144和1146站位甲烷浓度很高,其中1144站位最高达64982×10~(-6),以生物气为主,1146站位最高达85205×10~(-6),以热解气为主；1148站位甲烷浓度较低,以热解气为主；而1145站位甲烷浓度极低,因此从甲烷浓度来看1144、1146站位附近最有利于水合物的形成。孔隙水成分来看,1144站位没有发现氯浓度、盐度等指标明显变化,表明没有水合物存在；1146站位476m以下氯浓度和盐度明显下降,并与烃类气体含量明显增大相对应。可能与水合物有关。从烃类气体浓度变化和孔隙水成分变化来看,1148站位458～492m的滑塌层可能是气体和其它一些元素运移的盖层。
In recent years, marine hydrates have drawn great attention from scholars and scholars due to their potential huge resource value and environmental effects. The northern slope of the South China Sea is one of the key areas studied in China. Drilling carried out on the ODP 184 voyage in the northern South China Sea provided valuable first-hand information on hydrate studies in the area. Through the study of borehole data, it shows that the deposition rate on the east side of Dongsha is much higher than that on the west side, which is more favorable to the formation of hydrate. The concentrations of methane in stations 1144 and 1146 are very high, with the maximum of 64982 × 10 ~ (-6) at station 1144, mainly biogas, and the maximum of 1146 stations is 85205 × 10 ~ (-6) The main methane concentration is 1148, which is dominated by pyrolysis gas. However, the methane concentration at 1145 station is very low. Therefore, the formation of hydrate is most beneficial from the methane concentration point near 1144 and 1146 stations. In terms of pore water composition, there was no significant change of chlorine concentration and salinity at station 1144, indicating no hydrate existed. The concentration and salinity below 476 m at 1146 station obviously decreased and the content of hydrocarbon gas significantly increased correspond. May be related to hydrates. From the change of hydrocarbon gas concentration and pore water composition, the slippery layer of 458 ~ 492m in 1148 station may be the caprock of gas and some other elements migration.