煤层气储层物性预测的AVO技术对地震纵波资料品质要求的探讨  

The discussion of required P-wave quality for the AVO technology based on the CBM reservoir research

作　　者：常锁亮[1] 杨起[1] 刘大锰[1] 刘洋[2] 李国发[2] 索重辉[2] 

机构地区：[1]中国地质大学(北京) [2]中国石油大学(北京),北京102200

出　　处：《地球物理学进展》2008年第4期1236-1243,共8页Progress in Geophysics

基　　金：国家自然科学基金项目(40572091);国家高技术研究发展计划(863)项目(2007AA06Z218);国家重点基础研究发展计划课题项目(2006CB202202,2002CB211702);中国地质调查局项目(20021010004,1212010534702)资助

摘　　要：煤层的含气性及渗透性可以利用纵波AVO技术及基于各向异性理论的方位AVO技术进行研究.煤层气属于吸附气,储层厚度较薄,地震异常响应较弱,对地震资料的品质及其携带的信息量提出了更高的要求.本文对AVO与方位AVO反演理论的近似条件及模型试算结果进行了分析,提出了对地震纵波数据信噪比、入射角、偏移距分布及方位角分布等参数的要求：1.观测系统设计及野外采集时应保证地震波的有效入射角在0°～30°或更大范围内,偏移距应大中小均匀分布,避免过于集中或缺失.2.地震数据应有足够宽分布的方位角,煤层气地震勘探中应选择宽方位观测系统.3、地震资料信噪比应足够高.The gas content and permeability of coal can be researched by the technology of P-wave AVO and azimuthal AVO which based on the anisotropy theory. Because CBM is the roek-abosorbed gas, its reservoir is thin and its seismic anomalous response is weak, higher quality seismic data become essential and more important. In this paper, AVO and Azimuthal. AVO forward model trial calculation and inversion model approximate condition analyzing show that the CBM reservoir characters are more sensitive to the parameters of the S/N, distribution of angle of incidence, distribution of azimuth, distribution of offset of seismic data. So,1 it should be insured that the angle of incidence of the geometry is between 0°～30° or more, and the offset should be uniform distribution, 2 seismic data should be with a wide enough azimuth scope,3 the S/N should be high enough.

关 键 词：煤层气 含气性及渗透性 AVO与方位AVO 信噪比 入射角 方位角 

分 类 号：P631[天文地球—地质矿产勘探]