HQ-1PC站位位于琼东南盆地中部,对该站位沉积物孔隙水的地球化学分析发现其3～4m处有明显的盐度异常,说明该站位在沉积物浅表层有明显的高盐度流体加入.其他地球化学特征也显示在该深度有一亏损硫酸盐、富含碘的流体加入,这种流体特征与水合物形成时排放的高盐流体相似.在4m以下,HQ-1PC站位则表现出了明显的甲烷厌氧氧化特征,主要表现为浅的硫酸盐还原界限、高硫酸盐通量、高自生碳酸盐沉积等特征,同时在该深度以下碘也表现出了异常高的通量,暗示HQ-1PC站位所在区域具有高的有机质含量,微生物活动强烈,可为水合物的形成提供充足的气源.再结合明显的盐度异常特征,推测在该站位浅表层附近很有可能有天然气水合物生成,水合物在形成过程中排出的高盐流体及散逸出的甲烷气引起了一系列的地球化学异常现象. HQ-1PC station is located in the central Qiongdongnan basin. Geochemical analysis of pore water in this station shows obvious salinities at 3 ~ 4m, indicating that the station has obvious high salt content in shallow sediments Fluid addition Other geochemical features also show the addition of a depleted sulfate-rich, iodine-rich fluid at this depth that is similar in character to the high-salt fluid emitted during hydrate formation Below 4 m, the HQ-1 PC station Showed obvious methane anaerobic oxidation characteristics, mainly as a shallow sulfate reduction limit, high sulfate flux, high authigenic carbonate deposition characteristics, at the same time below the depth of iodine also showed unusually high Flux, implying that the region of HQ-1PC has high organic matter content and strong microbial activity, which can provide sufficient gas source for hydrate formation. Combined with obvious salinity anomalies, it is presumed that near the superficial surface of this station It is very likely that gas hydrate formation, hydration of high-salt fluids expelled during formation and evolution of methane gas caused a series of geochemical anomalies.