High-resolution Moho depth and V_(p)/V_(s) ratio distributions in northeast China from joint inversion of receiver functions and gravity data and their geological implications  

作　　者：Aowei HAO Haijiang ZHANG Shoucheng HAN Wenliang XU 

机构地区：[1]School of Earth and Space Sciences,University of Science and Technology of China,Hefei 230026,China [2]Anhui Mengcheng National Geophysical Observatory,Mengcheng 233527,China [3]Xi’an Mineral Resources Survey Center of China Geology Survey,Xi’an 710100,China [4]College of Earth Sciences,Jilin University,Changchun 130061,China

出　　处：《Science China Earth Sciences》2023年第7期1569-1582,共14页中国科学（地球科学英文版）

基　　金：supported by the National Key R&D Program of China(Grant No.2022YFF0800701);the National Natural Science Foundation of China(Grant No.U1839205)。

摘　　要：In this study,high-resolution Moho depth and average crustal V_(p)/V_(s) ratio distributions in northeast China were obtained through joint inversion of receiver functions and gravity data.The new joint inversion method comprehensively considers the complementary imaging strengths of the receiver functions in the vertical direction and the gravity data in the lateral direction.To a certain extent,it can reduce the adverse effects of the receiver function data caused by the sedimentary layers of the basin,the inclination of the Moho,and the structure heterogeneity below the station.In preprocessing the receiver function data,a regularized virtual station network was constructed using the teleseismic receiver function waveform reconstruction method to improve the overall spatial resolution.To filter the gravity data,the velocity structure-guided gravity filtering method and gravity upward continuation were used for the shallower region above the Moho and the deeper region below the lithosphere,respectively.The newly obtained model shows that the Moho depths of the Hailar Basin,Erlian Basin,Sanjiang Basin,and Bohai Bay Basin are slightly shallower than those of the surrounding areas,while the Moho depths of the Greater Xing’an Range,Lesser Xing’an Range,and Zhangguangcai Range are slightly deeper.Compared with previous results,the refined Moho depth distribution obtained in this study has a better correspondence with topographic relief and basin boundaries,and the contrast is more evident across the north-south gravity gradient lineament(NSGL).In the eastern part of the Songliao Basin,the Moho is relatively shallow,and there is a high V_(p)/V_(s) ratio,which may have been caused by the intrusion of hot mantle materials into the crust induced by lateral extension of the Songliao Basin.The high V_(p)/V_(s) ratio of the crust below the Changbaishan volcanic area implies the existence of partial melting in the crust caused by upwelling hot mantle materials.

关 键 词：Receiver functions GRAVITY Moho depth Vp/Vs ratio Northeast China 

分 类 号：P542[天文地球—构造地质学] P631.1[天文地球—地质学]