基于Sentinel-1A数据反演2015年新疆皮山Mw6.5地震断层滑动分布

摘要

In this study,a pair of SAR imagestaken before and after the Pishan earthquake acquired from the Sentinel-1A satellite are used to extract the coseismic deformation field.Based on the above coseismic deformation field and the Okada model,considering the varying incidence angle and unwrapping datum error,we inverse the fault slip distribution of this earthquake.The inversion results indicate that the Pishan earthquake is a thrust earthquake with smaller dip,the fault ruptures 5 km under the surface,and the maximum slip is about 0.76 m,and the main slip area is at the depth of 9-14 km.The estimated seismic moment is 5.14× 1018,approximately equivalent to the magnitude of Mw6.47.%使用Sentinel-1A卫星观测的2015年新疆皮山地震震前震后一对SAR影像,提取该地震的同震形变场.结合Okada位错模型,在考虑渐变入射角和解缠基准偏差的情况下,反演本次地震的断层滑动分布.结果表明,皮山地震是小倾角逆冲型地震,断层破裂开始于地表以下约5 km处,最大滑动量为0.76 m,高滑区集中于深度9～14 km,累计释放地震矩达5.14×1018,相当于矩阵级Mw 6.47.