Crustal structure using receiver function in the east part of A’nyêmaqên suture belt  

作　　者：段永红 张先康 刘志 徐朝繁 王夫运 潘纪顺 梁国经 

机构地区：[1]Geophysical Exploration Center, China Earthquake Administration [2]Longgang Volcano Observatory, Earthquake Administration of Jilin Province

出　　处：《Acta Seismologica Sinica(English Edition)》2007年第5期513-522,共10页

基　　金：Foundation item: National Natural Science Foundation of China (40334040 and 40474049).

摘　　要：Twenty broadband seismographs were deployed along Hongyuan, Sichuan to Wuwei, Gansu. 81 teleseismic events were recorded in one year. We computed receiver functions from teleseismic waveform data and obtained S wave velocity structure beneath each station along the profile by using receiver function inversion method. The results revealed that the crustal structure is very complex and crustal average S wave velocity is to be on the low side. Low velocity structure generally exists in the depth range of 10～40 km in the crust between Aba arc fault and northern edge fault of Qinling earth＇s axis and it is a tectonic feature of complex geological process such as ancient A＇nyemaqen Tethys ocean from closing and side colliding to subducted plate exhumed or thrust rock slice lifted. The Moho is about 50 km depth along the profile and is slightly deeper in the south than in the north.Twenty broadband seismographs were deployed along Hongyuan, Sichuan to Wuwei, Gansu. 81 teleseismic events were recorded in one year. We computed receiver functions from teleseismic waveform data and obtained S wave velocity structure beneath each station along the profile by using receiver function inversion method. The results revealed that the crustal structure is very complex and crustal average S wave velocity is to be on the low side. Low velocity structure generally exists in the depth range of 10～40 km in the crust between Aba arc fault and northern edge fault of Qinling earth＇s axis and it is a tectonic feature of complex geological process such as ancient A＇nyemaqen Tethys ocean from closing and side colliding to subducted plate exhumed or thrust rock slice lifted. The Moho is about 50 km depth along the profile and is slightly deeper in the south than in the north.

关 键 词：A＇nyemaqen surture belt receiver function velocity structure 

分 类 号：P313.2[天文地球—固体地球物理学]