机构地区: 中国石油大学北京资源与信息学院地质地球物理综合研究中心
出 处: 《石油地球物理勘探》 2011年第A01期17-26,163+167,共10页
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.