南海北部孔隙水碘与天然气水合物成藏关系研究  

Tracing the Gas Hydrate Reservoirs in the Northern South China Sea by Iodine Concentrations in Pore Waters from Marine Sediments

作　　者：傅飘儿[1] 曹珺[1] 刘纪勇[1] 王彦美[1] 张欣[1] 程思海[1] 

机构地区：[1]国土资源部海底矿产资源重点实验室,中国地质调查局广州海洋地质调查局,广州510075

出　　处：《地质论评》2016年第5期1344-1351,共8页Geological Review

基　　金：国家自然科学基金(编号:41606076);国土资源部海底矿产资源重点实验室开放基金项目(编号:KLMMR-2013-A-33)资助的成果~~

摘　　要：天然气水合物是一种重要的新型能源。然而,深海水合物具有埋藏深、作业难度大等特点,水合物难以被高效准确地识别,这已成为制约南海水合物地质调查的瓶颈之一。针对这一问题,本文结合近年来国际上新兴的碘及碘同位素方法,对南海北部台西南盆地两个站位的柱状沉积物（HD-86V和HD-109）开展了水合物成藏识别的研究。该沉积物孔隙水中碘离子含量分别介于8.3~132.0μmol/L和7.4~118.1μmol/L之间,远高于正常海水值（0.44μmol/L）。结合区域水合物勘查结果及甲烷含量特征,发现孔隙水碘离子含量与甲烷含量表现为显著的正相关关系。对比琼东南盆地及神狐工区等区域数据,均表明沉积物孔隙水碘离子含量在南海水合物成藏示踪方面具有良好的应用前景和推广价值。Objectives： As a new energy source, gas hydrate in marine has shown important economic significance. However, it is difficult to effectively and accurately identify the gas hydrate reservoirs, which has severely limited the geological survey for gas hydrate in the South China Sea. Previous studies indicated the iodine concentration in pore waters from marine sediments is a good tracer for gas hydrate. This study aims to identify relationship between the iodine concentration in pore water and the occurrence of gas hydrate reservoirs in the northern South China Sea. Methods：The pore water samples collected from sites HD-86V and HD-109 in the Southwest Taiwan Basin, which is one of the target areas for marine gas hydrate exploration in the northern South China Sea. The iodine concentration of samples was measured by ICP-MS at Stake Key Laboratory for Mineral Deposits Research, Nanjing University. Results ：The iodine concentrations in pore waters at sites HD-86V and HD-109 are 8.3 - 132 μmol/L and 7.4 118 μmol/L, respectively. Similar high iodine concentrations are also found in pore water at the Southeast Hainan Basin and Shenhu area, the northern South China Sea. Compared with the famous marine gas hydrate fields of the woad, the iodine concentrations of pore water from the northern South China Sea are slightly low, which may result from the shallow sampling depth in this study. In addition, the positive correlation between iodine concentrations of pore water and CH4 contents of headspace gas is found in marine sediments at Site HD-196A in the Southwest Taiwan Basin.

关 键 词：碘 孔隙水 海洋沉积物 天然气水合物 南海 

分 类 号：P618.13[天文地球—矿床学]