Effect of lateral heterogeneity on 2-D Rayleigh wave ZH ratio sensitivity kernels based on the adjoint method: Synthetic and inversion examples  

作　　者：Ting Lei HuaJian Yao Chao Zhang 

机构地区：[1]Laboratory of Seismology and Physics of the Earth’s Interior,School of Earth and Space Sciences,University of Science and Technology of China,Hefei 230026,China [2]Mengcheng National Geophysical Observatory,University of Science and Technology of China,Mengcheng 233500,China [3]Chinese Academy of Sciences Center for Excellence in Comparative Planetology,University of Science and Technology of China,Hefei 230026,China [4]College of Oceanography,Hohai University,Nanjing 245700,China

出　　处：《Earth and Planetary Physics》2020年第5期513-522,共10页地球与行星物理（英文版）

基　　金：This study was funded by the National Key R&D Program of China(2016YFC0600301,2018YFC1503400);the National Natural Science Foundation of China(41790464);Natural Science Foundation of Jiangsu Province of China(BK20190499);the Fundamental Research Funds for the Central Universities(2019B0071428).

摘　　要：The ratio between vertical and radial amplitudes of Rayleigh waves(hereafter,the Rayleigh wave ZH ratio)is an important parameter used to constrain structures beneath seismic stations.Some previous studies have explored crust and upper mantle structures by joint inversion of the Rayleigh wave ZH ratio and surface wave dispersion.However,all these studies have used a 1-D depth sensitivity kernel,and this kernel may lack precision when the structure varies a great deal laterally.Here,we present a systematic investigation of the two-dimensional(2-D)Rayleigh wave ZH ratio kernel based on the adjoint-wavefield method and perform two synthetic tests using the new kernel.The 2-D ZH ratio kernel is consistent with the traditional 1-D sensitivity kernel but has an asymmetric pattern with a preferred orientation toward the source.The predominant effect caused by heterogeneity can clearly be seen from kernels calculated from models with 2-D heterogeneities,which confirms the necessity of using the new 2-D kernel in some complex regions.Inversion tests using synthetic data show that the 2-D ZH ratio kernel has the potential to resolve small anomalies as well as complex lateral structures.

关 键 词：Rayleigh wave ZH ratio adjoint-wavefield method 2-D sensitivity kernel TOMOGRAPHY 

分 类 号：P631.4[天文地球—地质矿产勘探]