基于叠前黏滞—弥散波动方程的数值模拟  

Numerical simulation based on prestack diffusiveviscous wave equation

作　　者：胡军辉[1,2] 文晓涛[1] 杨小江 贺振华[2] 孙瑶[1,2] 陈程[1,2] 陈仁豪 

机构地区：[1]成都理工大学地球探测与信息技术教育部重点实验室,四川成都610059 [2]成都理工大学油气藏地质及开发工程国家重点实验室,四川成都610059 [3]中海石油总公司深圳分公司,广州深圳510240

出　　处：《石油地球物理勘探》2014年第4期708-714,4,共7页Oil Geophysical Prospecting

基　　金：国家自然科学基金(41174115);国家自然科学基金青年基金(40904034);国家重大专项(2011ZX05005-003)等项目联合资助

摘　　要：地震响应中的低频阴影现象与含油气储层有很大关联,针对含流体储层提出的黏滞—弥散波动方程理论能较好地模拟两者之间的关系。本文将叠前数值模拟与该理论相结合,定量地分析了黏滞—弥散理论中不同参数对地震响应的影响:1黏滞系数越大,地震波能量衰减越大,高频成分衰减越剧烈;2弥散系数越大,地震波能量衰减越大,衰减与频率无关;3品质因子越小,地震波相位变化越大。在此基础上,定性地给出了低频阴影现象与黏滞系数、弥散系数、储层厚度之间的关系。另外,本文还探讨了低频阴影形成机理、相速度—频散关系式中存在的问题及如何分解薄储层的调谐问题。Low-frequency shadow in seismic data has a close relation with fluid reservoirs.The diffusiveviscous theory can extremely simulate the relationship between them.We combine prestack wave equation numerical simulation with this theory,and analyze quantitatively impacts of different coefficients in diffusive-viscous theory on seismic response.The following observations are obtained:1Seismic energy,especially high-frequency component,attenuates with the increase of viscous coefficient;2Seismic energy attenuates with the increase of diffusion coefficient,but this attenuation has no relations with frequency;3The smaller quality factor Qis,the bigger phase shift seismic wave has.We calculate qualitative relationships between low-frequency shadow,diffusion,viscous,and reservoir thickness based on this analysis.In addition,this paper discusses the formation mechanism of low-frequency shadow,phase velocity dispersion equation,and seismic wave tuning for thin reservoir identification.

关 键 词：叠前数值模拟 黏滞—弥散波动方程 地震响应 低频阴影 调谐 衰减 含流体储层 

分 类 号：P631[天文地球—地质矿产勘探]