Double-sided subduction with contrasting polarities beneath the Pamir-Hindu Kush:Evidence from focal mechanism solutions and stress field inversion

作     者：Yu Yang Zuoxun Zeng Scott D.King Xiao Shuang Yu Yang;Zuoxun Zeng;Scott D.King;Xiao Shuang

作者机构：School of Earth SciencesChina University of Geosciences(Wuhan)Wuhan 430074China Huazhong Tectonomechanical Research CenterChina University of Geosciences(Wuhan)Wuhan 430074China Department of GeosciencesVirginia TechBlacksburgVA 24061USA Fuyang Branch of Hangzhou Bureau of Planning and Natural ResourcesHangzhou 311499China 

出 版 物：《Geoscience Frontiers》 (地学前缘（英文版）)

年 卷 期：2022年第13卷第4期

页      面：98-113页

核心收录：

学科分类：070801[理学-固体地球物理学] 07[理学] 0708[理学-地球物理学] 

基　　金：jointly supported by National 985 Platform construction project,China Geological Survey(Grant No.12120114002211) National Nature Science Foundation of China(Grant No.41230206) a fund of the Graduate School of the China University of Geosciences for visiting and conducting research abroad 

主　　题：Pamir-Hindu Kush Seismicity Stress field Double-sided subduction Low-velocity body 

摘      要：The Pamir-Hindu Kush region at the western end of the Himalayan-Tibet orogen is one of the most active regions on the globe with strong seismicity and deformation and provides a window to evaluate continental collision linked to two intra-continental subduction zones with different *** seismicity and seismic tomography data show a steep northward subducting slab beneath the Hindu Kush and southward subducting slab under the ***,we collect seismic catalogue with 3988 earthquake events to compute seismicity images and waveform data from 926 earthquake events to invert focal mechanism solutions and stress field with a view to characterize the subducting slabs under the Pamir-Hindu Kush *** results define two distinct seismic zones:a steep one beneath the Hindu Kush and a broad one beneath the *** and intermediate-depth earthquakes are mainly distributed in the Hindu Kush region which is controlled by thrust faulting,whereas the Pamir is dominated by strike-slip stress regime with shallow and intermediate-depth *** area where the maximum principal stress axis is vertical in the southern Pamir corresponds to the location of a highconductivity low-velocity region that contributes to the seismogenic processes in this *** interpret the two distinct seismic zones to represent a double-sided subduction system where the Hindu Kush zone represents the northward subduction of the Indian plate,and the Pamir zone shows southward subduction of the Eurasian plate.A transition fault is inferred in the region between the Hindu Kush and the Pamir which regulates the opposing directions of motion of the Indian and Eurasian plates.