摘要
地震叠前反演是获取地下介质弹性参数的主要手段.常规的非线性AVO反演方法多使用梯度下降类优化算法,需要计算目标函数的梯度方程,准确性和效率较低.针对此问题,本文提出一种基于伴随状态方程梯度计算的纵、横波阻抗及密度三参数反演方法,在AVO反演公式的基础上推导了目标函数梯度的伴随状态方程,引入精度、效率优于常规优化算法的有限内存的拟牛顿优化算法(Limited memory-BFGS,即L-BFGS)求解反演目标函数.通过1-D、2-D模型数据及实际测井数据测试,证实该方法能够反演获得精确的纵、横波阻抗、密度及纵-横波速度比,抗噪性测试证实该方法对噪声的容许程度为信噪比大于约8~15 dB.将该方法应用于致密砂岩储层实际地震资料,所得结果与测井数据吻合度高,且能够反映横向地层展布规律,证实了该方法的有效性.
Seismic pre-stack inversion is the key method to obtain the elastic parameters of underground media.The conventional non-linear AVO inversion methods often utilize gradient descent-based optimization algorithms,which require the computation of gradient equation for the objective function,resulting in relatively low accuracy and efficiency.To solve this problem,a three-parameters inversion method of P-wave impedance,S-wave impedance and density based on the gradient calculation of adjoint state equation is proposed in this paper.In this method,the adjoint state equation of the objective function gradient is derived based on the AVO inversion formula.Furthermore,a quasi-Newton optimization algorithm with Limited memory-BFGS(L-BFGS)is introduced to solve the inverse objective function.The 1-D,2-D model and actual logging data is used to test the method,and the results show that this method can obtain accurate P-wave,S-wave impedance,density and PSwave velocity ratio.Additionally,noise resistance testing demonstrated that the method can tolerate a signal-tonoise ratio(SNR)above approximately 8~15 dB.Finally,the method is applied to the actual seismic data of tight sandstone reservoir,and the results exhibited a high consistency with well logging data and effectively captured the lateral distribution patterns of the strata,thereby validating the effectiveness of the method.
作者
宫菡婕
刘致水
高飞
包乾宗
Honggeun Jo
张嘉豪
GONG HanJie;LIU ZhiShui;GAO Fei;BAO QianZong;Honggeun Jo;ZHANG JiaHao(College of Geological Engineering and Geomatics,Chang’an University,Xi’an 710054,China;Research Institute of Shanxi Yanchang Petroleum Group Co.,Ltd.,Xi’an 710075,China;Department of Energy Resources Engineering,Inha University,Incheon 22212,South Korea)
出处
《地球物理学报》
北大核心
2026年第2期857-872,共16页
Chinese Journal of Geophysics
基金
国家自然科学基金项目(42474161,42442402,42104120)
长安大学青年学者学科交叉团队项目(300104240917)资助.
关键词
AVO非线性反演
三参数反演
阻抗反演
伴随状态方程
致密砂岩储层
AVO non-linear inversion
Three-parameter inversion
Impedance inversion
Adjoint equation of state
Tight sandstone reservoir
