基于波阻抗反演的天然气水合物地震检测技术  

The Seismic Detecting Technique on Gas Hydrates Based on Wave Impedance Inversion

作　　者：沙志彬[1,2] 郑涛[2] 杨木壮[3] 王明君[4] 梁金强[2] 苏丕波[5] 陈晓宇[6] 

机构地区：[1]中国地质大学资源学院,湖北武汉430074 [2]广州海洋地质调查局,广东广州510760 [3]广州大学地理科学学院,广东广州510006 [4]中国地质科学院矿产资源研究所,北京100037 [5]厦门大学海洋与环境学院近海海洋环境国家重点实验室,福建厦门361005 [6]中国地质大学地球科学与资源学院,北京100083

出　　处：《现代地质》2010年第3期481-488,共8页Geoscience

基　　金：国家高技术研究发展计划项目(2006AA09A202);国土资源部公益性行业科研专项项目(200811014);国土资源部海洋油气资源与环境地质重点实验室资助项目(MRE200911);国家重点基础研究发展计划项目(2009CB219502)

摘　　要：天然气水合物作为特殊的地质体,可以有效地粘结碎屑颗粒,降低沉积物孔隙度,它的存在改变了地层沉积物的物理性质,造成天然气水合物与围岩速度反差较大,从而与围岩之间存在明显的波阻抗差。为了对地层中是否有天然气水合物赋存进行地震检测,对南海北部神狐海域的天然气水合物赋存区域的地震资料进行波阻抗反演分析,结果显示波阻抗反演方法能够作为探测天然气水合物的一种技术手段,研究区天然气水合物矿体的波阻抗呈高值分布特征,波阻抗值约为3 850~3 960 g/cm3.m/s。综合分析认为,波阻抗反演方法能够用于天然气水合物的地震探测、储层分析和综合研究工作中,反演结果可以为天然气水合物储量计算提供比较准确的矿体面积和厚度参数。As specific geologic body,gas hydrate can cement effectively clastic particles and reduce porosity of deposition,so its presence changes physical property of the sedimentary strata and results in the difference of seismic-wave velocity between gas hydrate and the surrounding rock,and there exists obviously wave impedance difference.In order to detect the presence of sediments with gas hydrate,seismic data of gas hydrate zone in the Shenhu area of the northern South China Sea were used in the wave impedance inversion through practice,testing and summary.Wave impedance inversion method is considered as a kind of good seismic detection technique for identification of gas hydrates,meanwhile,the wave impedance of gas hydrate zone shows high value in the study area,and the wave impedance value is about 3,850-3,960 g/cm3·m/s.All the results suggested that wave impedance inversion can be used for detection,reservoir analysis and comprehensive research of gas hydrates.The wave impedance inversion results can provide comparatively accurate area and thickness parameters of gas hydrate zone for reserves calculation.

关 键 词：天然气水合物 波阻抗反演 地震检测 

分 类 号：P631.4[天文地球—地质矿产勘探]