VSP各向异性矢量波场分离方法研究及其应用  

Method and application of VSP anisotropic vector wavefiled decomposion

作　　者：孙赞东[1,2] 李强[1,2] 孙文博[1,2] 白海军[1,2] 

机构地区：[1]中国石油大学(北京)地质地球物理综合研究中心,北京昌平102249 [2]中国石油大学(北京)油气资源与探测国家重点实验室,北京昌平102249

出　　处：《石油地球物理勘探》2011年第A01期17-26,163+167,共10页Oil Geophysical Prospecting

基　　金：国家重点基础研究发展规划973项目(2011CB201103)"中国西部叠合盆地深部有效碳酸盐岩储层形成机制与分布预测";国家油气重大专项(2011ZX05004003)"海相碳酸盐岩储层地震描述与油气藏有效预测技术研究"资助

摘　　要：本文介绍了一种基于各向异性(TI)介质假设的非零井源距三维三分量VSP矢量波场分离方法。该方法将经过一次旋转的共炮点数据,使用非线性约束SQP算法反演求得检波点附近的各向异性Thomsen参数,根据介质的各向异性性质,计算每个波场(上、下行纵波和上、下行横波)的传播角度、慢度和极化矢量。在频率域使用正则化的最小广义逆算法求出每种波的傅里叶振幅分量,再反变换到时间域得到分离后的各种波场。通过对非零井源距三分量VSP模型试算、实际资料处理以及与各向同性参数反演矢量法结果对比分析,验证了该方法的可行性和优越性。This paper introduces a vector wave field separation method for 3D 3C VSP data which is under anisotropic hypothesis.Using the common shot 3C data rotated once,the anisotropic Thomsen's parameters at the downhole receivers are inverted by using a nonlinear SQP method.After computing propagation angle,slowness and polarization vectors for each plane wave(upgoning P,downgoing P,upgoing S and downgoing S wave),a regularized generalized inverse algorithm in frequency domain is applied to determine the Fourier plane-wave amplitudes.Wave filed separation in time domain is realized by inverse Fourier transform.The feasibility and stability of the method is proven by application to two forward modeled VSP data and one field zero-offset 3C VSP data.Additionally,the superiority of this algorithm is shown by comparison of this algorithm with the isotropic vector inversion method.

关 键 词：VSP 波场分离 SQP 各向异性 THOMSEN参数 慢度 波场分离 

分 类 号：P631[天文地球—地质矿产勘探]