Zoeppritz方程叠前多参数反演及密度敏感性分析  

Density-sensitivity analysis about prestack multi-parameter inversion based on the exact Zoeppritz equation

作　　者：郭强 张宏兵[1] 曹呈浩 韩飞龙 尚作萍[3] 

机构地区：[1]河海大学地球科学与工程学院,江苏南京210098 [2]中科院地质与地球物理研究所,北京100029 [3]河海大学力学与材料学院,江苏南京210098

出　　处：《石油地球物理勘探》2017年第6期1218-1225,共8页Oil Geophysical Prospecting

基　　金：国家自然科学基金项目(41374116;41674113);中国海洋石油总公司科研项目(CNOOC-KJ125ZDXM 07LTD NFGC 2014-04)联合资助

摘　　要：基于Zoeppritz方程或其近似公式的叠前地震反演应用广泛,但多参数(尤其是密度参数)的同步反演结果不稳定。通过边界保护正则化和马尔科夫随机域的软约束建立反演目标函数,采用精确Zoeppritz方程进行反演,并使用快速模拟退火算法解非线性优化问题。数值结果表明,在小角度时,密度参数对角度变化不敏感,但对反射系数绝对值变化的贡献度最大;二维合成数据测试结果表明,该反演算法采用小角道集可以反演出满意的密度结果;实际资料反演结果提供了详细的地层信息,且与测井数据基本吻合。Prestack seismic inversion based on the exact Zoeppritz equation and its approximations has been widely adopted but complicated problems remain.Multi-parameter inversion results are unstable,especially for the parameter of density.We develop an inversion method by constructing a new objective function which includes the edge-preserving regularization and soft constraints based on Markov random domain.We apply the fast simulated annealing algorithm to solve the nonlinear optimization problem based on the exact Zoeppritz equation.Numerical results indicate that the density is insensitive to angle variation within small incidence angle range,but it makes more contribution to the reflectivity magnitude variation.Test results on 2-D synthetic data demonstrate that a satisfactory inverted density result can be achieved within small incidence angles with the proposed approach.Field data inverted results provide detailed stratigraphic information wellmatched with logging data over most parts.

关 键 词：叠前多参数反演 密度敏感性 Zeoppritz方程 边界保护正则化 马尔科夫随机域 

分 类 号：P631[天文地球—地质矿产勘探]