南海北部陆坡区沉积与天然气水合物成藏关系

截止2007年底,世界上已直接或间接发现水合物的矿点共有132处。另外,许多地方见有生物及碳酸盐结壳标志。世界上取得天然气水合物样品的地区表明,其形成与分布除了需要特定的温压条件外,还与沉积条件有较为密切的关系。2007年5月,我国在南海北部海域成功钻获天然气水合物实物样品,证实了南海北部蕴藏有丰富的水合物资源。通过对南海中北部陆坡区地层的地震相和沉积相分布特征、层序地层和沉积体系的综合分析,总结其沉积层序的特征,并对该区域沉积条件与水合物聚集成藏的关系进行了探讨。

RELATION BETWEEN SEDIMENTATION AND GAS HYDRATE RESERVOIRS IN THE NORTHERN SLOPE OF SOUTH CHINA SEA

Until the end of 2007, 132 gas hydrate sites have been directly found or inferred worldwide with many locations showing biological markers and carbonate mass. In the gas hydrates bearing sediments,formation and distribution of gas hydrates are mainly controlled by specified pressure and temperature,and they are also often associated with sedimentary conditions. In May 2007, gas hydrate cores were successfully recovered in the northern slope of South China Sea, conforming the existence of vast gas hydrate resources. Through the studies of distribution characteristics of seismic facies and sedimentary facies,together with data of sequence stratigraphy and sedimentary system in the sediments of central northern slope of South China Sea, we identify features of sedimentary sequences and further analyze and discuss relation between sedimentary conditions and accumulation of gas hydrate reservoirs in this region.