基于测井与地震多属性分析神狐海域天然气水合物分布特征  

DISTRIBUTION OF GAS HYDRATE IN SHENHU AREA:IDENTIFIED WITH WELL LOG AND SEISMIC MULTI-ATTRIBUTES

作　　者：靳佳澎 王秀娟[1,3] 陈端新 郭依群[4] 苏丕波 梁金强[4] 钱进[1,3] 

机构地区：[1]中国科学院海洋研究所,青岛266071 [2]中国科学院大学,北京100049 [3]海洋国家实验室海洋矿产资源评价与探测技术功能实验室,青岛266071 [4]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510301

出　　处：《海洋地质与第四纪地质》2017年第5期122-130,共9页Marine Geology & Quaternary Geology

基　　金：中国地质调查局南海水合物勘探项目(DD20160211);国家自然科学基金项目(41676041,41676040)

摘　　要：我国在神狐海域钻探发现了高饱和度天然气水合物,由于该地区受迁移峡谷影响,水合物在空间的分布变化较大。本文把测井数据和地震数据相结合识别了BSR并解释了侵蚀面等层位,沿水合物稳定带底界提取多种属性,并对属性结果进行优化分析。发现振幅类属性对水合物显示较为敏感,不同站位水合物矿体展布特征不同。在W19井和SC-02井水合物矿体呈马蹄状分布,W18井矿体呈斑点状分布,分别位于埋藏水道天然堤的局部高点和水道头部高点上,矿体形态与构造高点形态一致。测井异常指示的水合物层在SC-02井伽马值较高,而W18和W19井水合物层伽马值较低,表明不同站位含水合物层泥质含量不同。而地震解释和属性分析发现水合物层位于一个规模较大的气烟囱构造上部,流体运移是控制该区域水合物成藏的重要条件,气体组成分析表明热成因气为水合物的成藏提供重要气源。High quality gas hydrate samples have been successfully recovered from the Shenhu area,the northern slope of South China Sea.The spatial distribution of gas hydrate varies greatly owing to the complex fluid movement caused by lateral migration of canyons and gas chimneys.In this paper,we identified the BSR and erosional canyon surface with well logging and seismic data and the extracted multiple seismic attributes along the theoretical base of the gas hydrate stability zone（BGHSZ）.It is found that the amplitude type of attributes are sensitive to gas hydrate after optimization of all extractable seismic attributes.Description of gas hydrate bodies suggests that the distribution pattern of gas hydrate changes from site to site.It is horseshoe-shaped at Site W19 and U-shaped and point-shaped at Site W18 respectively,depending upon the topography of the local structural high.Gas hydrate occurrences are inconsistent with lithology according to well log data.It is mainly distributed at the top of a large gas chimney structure.Fluid flow is an essential element for gas hydrate deposition in this area,and thermogenic gas contributes to higher gas hydrate saturation.

关 键 词：天然气水合物 振幅属性 空间分布 侵蚀面 神狐海域 

分 类 号：P738[天文地球—海洋地质]