南中国海神狐海域天然气水合物地震识别及分布特征  

Seismic identification of gas hydrate and its distribution in Shenhu Area,South China Sea

作　　者：徐华宁[1,2] 杨胜雄[2] 郑晓东[3] 王明君[4] 王家生[1] 

机构地区：[1]中国地质大学(武汉)地球科学学院,武汉430074 [2]广州海洋地质调查局,广州510075 [3]中国石油勘探开发科学研究院,北京100083 [4]中国地质科学院矿产资源研究所,北京100037

出　　处：《地球物理学报》2010年第7期1691-1698,共8页Chinese Journal of Geophysics

基　　金：国家重点基础研究计划973项目(2009CB219500);国家高技术研究发展计划863项目(2006AA09A202)联合资助

摘　　要：南中国海北部陆坡神狐海域是天然气水合物发育的有利地区,钻井取芯表明此区域的天然气水合物以细颗粒状分布于水合物稳定带内.以三维地震数据为基础,讨论海洋天然气水合物调查的高分辨率地震成像关键技术,综合利用不同的地球物理方法(阻抗反演、属性聚类分析及神经网络方法等),以钻井结果为约束分析不同方法对天然气水合物识别的适用性,确定利用属性聚类方法来获得神狐海域天然气水合物与游离气的三维空间展布特征.将钻井取芯结果与地质条件相结合,综合多方面地球物理信息,分析产生这一分布特征的地质原因,指出断层与裂缝是南海北部陆坡神狐海域水合物、游离气的分布模式及天然气水合物形成的主要地质控制因素.Shenhu Area of Northern South China Sea has favorable conditions for the occurrence and formation of gas hydrate, which was within the hydrate stable zone （HSZ）. discovered in drilling cores and disseminated evenly Based on 3-D seismic data of marine geophysical investigation of gas hydrate, a variety of methods on gas hydrate identification were introduced, including high-resolution seismic imaging, impedance inversion, seismic attribute cluster analysis and neural network analysis. The applicability of various techniques was discussed and comprehensive interpretation of the results indicates that seismic attribute cluster analysis is the optimal technique for gas hydrate identification,by which the 3-D distribution of free gas and gashydrate is presented and is identical with the drilling cores. Integrating the drilling cores with geological conditions, various geophysical information was used to analyze the geological cause of formation and the distributing model of free gas and gas hydrate, from which it can be concluded that faults and fractures are the important if not dominant factor in the formation and distribution of gas hydrate in Shenhu Area.

关 键 词：南中国海 神狐海域 天然气水合物 地震成像 地震属性 分布模式 

分 类 号：P315[天文地球—地震学] P631[天文地球—固体地球物理学]