摘要
针对2021年5月22日青海玛多县Ms7.4地震震区形变信息、形变特征以及滑动断裂特性的提取与模拟等问题,获取了玛多县地震区的Sentinel-1A影像,采用双轨差分干涉法,并优化各项参数,提取出同震形变场,利用slipBERI(slip from bayesian regularized inversion)方法对断层的几何参数及形变场进行反演和模拟。结果表明:玛多地震同震形变场的形状近似于一个椭圆,断层整体呈西北-东南走向,其上部为沉降区,下部为隆升区,最大视线向(line of sight,LOS)形变分别为0.65 m和0.81 m。地震形变场的运动主要以东西方向的水平运动为主,并伴有明显的左旋走滑,断层上下方相对视线向运动可达1.50 m,表明此次地震的地表破裂有明显的错位移动。通过分析形变信息和地表破裂特征,可以判断该破裂带位于巴颜喀拉块体,为昆仑山口-江口断裂,反演结果与观测结果相符,这表明观测结果较可靠。
Aiming at the extraction and simulation of the deformation information,deformation characteristics and sliding fault characteristics of the Ms7.4 earthquake that occurred in Maduo County,Qinghai on May 22,2021.In this contribution,the Sentinel-1A images of the Maduo County earthquake region were obtained,and the seismic deformation field was extracted by using the dual-track differential interferometry and optimizing the parameters.The slipBERI(slip from bayesian regularized inversion)method was used to invert and simulate the geometrical parameters and deformation field of the fault.The results show that the appearance of the co-seismic deformation field of this earthquake is approximately an ellipse,and the whole fault shows a northwest-southeast trend,with a subsidence area above and a uplift area below.The maximum LOS deformation is 0.65 m and 0.81 m respectively.The seismic deformation field is dominated by horizontal movement in the east-west direction,showing obvious left-handed strike-slip characteristics.The relative LOS movement on both sides of the fault can reach 1.50 m,which reflects the obvious dislocation displacement of the surface rupture of the earthquake.By analyzing deformation information and surface fracture characteristics,it can be judged that the rupture zone which is located in the Bayan Har blockis the Kunlun Pass-Jiangkou fault.The inversion results are consistent with the observations,which indicates that the observations are more reliable.
作者
付玉蒂
薛东剑
张小轩
FU Yu-di;XUE Dong-jian;ZHANG Xiao-xuan(College of Earth Science,Chengdu University of Technology,Chengdu 610059,China)
出处
《科学技术与工程》
北大核心
2023年第22期9370-9377,共8页
Science Technology and Engineering
基金
四川省科技计划(2019YJ0505)
青海省青藏高原北部地质过程与矿产资源重点实验室开放课题(2019-KZ-02)
青海省科技计划(2019-SF-130)。
