基于旋转交错网格的TI介质二维三分量面波模拟  

Numerical simulation of 2D three-component surface waves in TI media based on the rotated staggered grid

作　　者：魏皓 童思友[1,2] 辛成庆 袁士川 王金刚 徐秀刚 WEI Hao;TONG Siyou;XIN Chengqing;YUAN Shichuan;WANG Jingang;XU Xiugang(MOE and College of Marine Geosciences,Ocean University of China,Qingdao,Shandong 266100,China;Laboratory for Marine Mineral Resources,Qingdao National Laboratory for Marine Science and Technology,Qingdao,Shandong 266237,China;Department of Earth and Space Sciences,Southern University of Science and Technology,Shenzhen,Guangdong 518055,China)

机构地区：[1]中国海洋大学海洋地球科学学院,山东青岛266100 [2]崂山实验室海洋矿产资源评价与探测技术功能实验室,山东青岛266237 [3]南方科技大学地球与空间科学系,广东深圳518055

出　　处：《石油地球物理勘探》2024年第5期1022-1036,共15页Oil Geophysical Prospecting

基　　金：国家自然科学基金面上项目“OBN地震勘探检波点动态定位及基于深度学习的波场分离技术研究”(42074140)资助。

摘　　要：基于标准交错网格(Standard Staggered Grid,SSG)的有限差分法在面波的正演模拟中应用广泛。单一的瑞利波或勒夫波模拟已不能满足横向各向同性(TI)介质中面波模拟的需求。为此,提出一种基于旋转交错网格(Rotated Staggered Grid,RSG)的TI介质二维三分量面波模拟方法。首先,采用一阶速度—应力二维三分量波动方程将P-SV波方程和SH波方程联合;其次,将RSG有限差分法结合多轴完美匹配层技术,实现包含瑞利波和勒夫波的二维三分量面波模拟;然后从波前快照、波形曲线和频散曲线三个方面,定性和定量地对比RSG和SSG有限差分法在二维各向同性介质均匀半空间面波模拟的效果和精度;最后,将所提方法应用在均匀半空间TI介质(包括VTI、HTI和TTI)和两层速度递增TTI介质的二维三分量面波模拟,通过波场快照、地震记录和频散能量图分析TI介质中的面波特征和各向异性参数对面波频散特征的影响。实验分析结果证明了文中方法在面波模拟实践中的适用性,为二维全波场地震波模拟甚至是全波场反演提供了重要参考,对进一步认识各向异性介质中面波的传播特征具有重要意义。The finite difference method based on a standard staggered grid is widely used in the forward simulation of surface waves.The single use of the Rayleigh or the Love wave simulation method is no longer able to meet the surface wave simulation needs in the context of transversely isotropic(TI)media.Therefore,a two-dimensional three-component surface wave simulation method based on a rotated staggered grid(RSG)for TI media is proposed.Firstly,the first-order velocity-stress two-dimensional three-component wave equation is adopted to combine the P-SV wave equation and SH wave equation.Next,the RSG finite difference method is combined with multi-axis perfectly matched layer technology to implement a two-dimensional three-component surface wave simulation including Rayleigh wave simulation and Love wave simulation.Then,qualitatively and quantitatively compare the effect and accuracy of the RSG finite difference method and the standard staggered grid(SSG)finite difference method in the simulation of surface waves in two-dimensional isotropic homogeneous half-space media,in three aspects of wavefront snapshots,waveform curves,and dispersion curves.Finally,this method is applied to the two-dimensional three-component surface wave simulation in homogeneous half-space TI media(including VTI,HTI,and TTI)and two-layer velocity-increasing TTI media.Through wavefield snapshots,seismic records,and dispersion energy diagram,the characteristics of surface waves in TI media and the effect of anisotropic parameters on surface wave dispersion characteristics are analyzed.The experimental analysis realizes the simulation of Rayleigh wave and Love wave with the same equation,which proves the applicability of the proposed method in surface wave simulation practice,and provides an important reference for full-wave seismic wave simulation and even full-wave field inversion in two-dimensional cases.Moreover,it is of great significance for further understanding the propagation characteristics of surface waves in the anisotropic media.

关 键 词：面波模拟 有限差分 二维三分量 TI 介质 频散 

分 类 号：P631[天文地球—地质矿产勘探]