摘要
实际地下介质具有黏滞性,因此在全波形反演中必须考虑吸收衰减效应。本文从基于广义标准线性固体(GSLS)模型的黏弹性波动方程出发,得到一阶速度—应力黏声波方程,并推导出相应的纵波速度梯度计算公式;再采用高阶交错网格有限差分法和共轭梯度法,实现了基于一阶速度—应力黏声波方程的二维时间域黏声波全波形反演方法。模型测试结果表明:与未考虑吸收衰减效应的纵波速度反演结果相比,采用本文方法能得到更准确的纵波速度反演结果。
Real earth media are characterized by the visco-elasticity,so it is necessary to consider the absorption and attenuation effects in the full waveform inversion.In this paper,we propose a visco-acoustic wave full waveform inversion in the 2 D time-domain.According to the visco-elastic wave equation based on generalized standard linear solid(GSLS)model,a first-order velocity-stress visco-acoustic wave equation is obtained.Then the corresponding P-wave velocity gradient is derived.Based on high-order staggered-grid finite-difference method and conjugate gradient method,the visco-acoustic full waveform inversion in the 2 Dtime domain based on first-order velocity-stress visco-acoustic wave equation is realized.Numerical examples demonstrate the effectiveness of the proposed method.Compared with other methods without considering the absorption and attenuation effects,the P-wave velocity inversion results with the proposed method are much more accurate.
出处
《石油地球物理勘探》
EI
CSCD
北大核心
2018年第1期87-94,共8页
Oil Geophysical Prospecting
基金
中国石油天然气股份有限公司科技项目"裂缝综合识别与评价新技术及软件开发(2015B-3712)"
中国石油天然气集团公司科技项目"非均质储层地震预测与流体检测技术(2016A-3303)"联合资助
关键词
黏弹性介质
广义标准线性固体
黏声波方程
共轭梯度法
全波形反演
visco-elastic medium
generalized standard linear solid
visco-acoustic wave equation
conjugate gradient
full waveform inversion
