基于各向异性岩石物理的缝隙流体因子AVAZ反演  

AVAZ inversion for fluid factor based on fracture anisotropic rock physics theory

作　　者：陈怀震 印兴耀[1] 高成国[2] 张广智[1] 陈娇娇 

机构地区：[1]中国石油大学(华东)地球科学与技术学院,青岛266555 [2]新疆油田勘探开发研究院,新疆克拉玛依834000

出　　处：《地球物理学报》2014年第3期968-978,共11页Chinese Journal of Geophysics

基　　金：国家重点基础研究发展计划"973"项目(2013CB228604;2014CB239201);国家油气重大专项(2011ZX05014-001-010HZ);中央高校基本科研业务费专项资金资助(14CX06015A);中国石化地球物理重点实验室开放研究基金资助

摘　　要：裂缝型储层表现出较强的各向异性特征.缝隙中充填不同流体时,裂缝储层的地震响应特征也不相同.本文从各向异性岩石物理模型出发,引入可有效识别缝隙流体的指示因子,并研究缝隙充填流体类型、饱和度以及缝隙纵横比与流体因子的相互关系,进而分析不同流体充填时介质的地震响应特征,并基于AVAZ反演方法估测缝隙流体指示因子.首先对缝隙流体因子的敏感性进行了分析,讨论当缝隙充填不同流体时,缝隙流体因子值的变化特征,同时研究了不同流体类型充填时裂缝储层反射系数随方位角和入射角的变化特征.某工区测井数据和复杂裂缝模型应用表明,基于各向异性岩石物理的缝隙流体因子AVAZ反演方法合理、可靠,且具有良好的抗噪性,即当对合成地震记录添加信噪比不小于1/2的随机噪声时,利用AVAZ反演方法估测所得流体因子值与真实值仍然吻合较好.The fractured reservoirs show strong anisotropy. When the fracture is filled with different types of fluids, the seismic response characteristics of fractured reservoir are not the same. Starting from the anisotropic rock physics theory, this article introduces the identification factor that can effectively distinguish fracture fluid; studies the relationship of fluid factor to fluid types, saturation and crack aspect ratio; analyzes the seismic response characteristics when the fracture is full of different fluids; and ultimately puts forward the method to estimate the crack fluid factor based on AVAZ inversion. Firstly, the sensitivity of crack fluid factor is analyzed in this paper. Secondly, the features of fluid factor and fractured reservoir＇s reflection coefficient variation when the fracture is filled with different types of fluids are discussed. At last, well-log data and complex fracture model are used to verify the inversion method. The results show that the method to estimate the crack fluid factor is reasonable and reliable. And the estimation results of the fluid factor can match the true value well when the synthetic seismic traces contain a random noise.

关 键 词：裂缝 流体因子 岩石物理 方位角道集 各向异性 叠前反演 

分 类 号：P631[天文地球—地质矿产勘探]