基于IGS观测数据的智利Mw8.2级地震分析

Analysis of Chile Mw8.2 Earthquake Based on Observations of IGS Stations

利用2014年智利Mw8.2级地震前后各3d的震中周边40个IGS站的连续观测数据和IGS精密星历,计算获得远场同震地表位移,结果显示,智利地震同震水平位移影响范围达1 500 km^2 000 km;经过对其中2个IGS站的高频观测数据进行解算,获得地震发生瞬时测站动态运动轨迹,在此基础上,使用S变换,过滤背景噪声,有效拾取P波初至时刻,反演出P波在地壳中的传播速度,并与IRIS提供的参考值进行对比和分析,说明结果的可靠性。

Based on IGS precise ephemeris and 3-day IGS observations before and after the great Mw 8.2 Chile earthquake ,we presented the coseismic deformation field composed of 40 sites for Indonesia and surrounding area .The results show that the scope of co-seismic horizontal displacement up to 1500-2000 km;we solved high-frequency obser-vations of 2 IGS stations to obtain the dynamic trajectory ,furthermore ,we used the S-transform algorithm for background noise Filtering and the primary wave （P-wave） arrival picking from high-rate GPS seismic waves,inversed the P-wave propagation velocity in the earth＆#39;s crust,we compared and analyzed it with reference values provided by IRIS （Incorporat-ed Research Institutions for Seismology ） to illustrate the reliability of the result .The results of research could be used for GNSS data monitoring and forecasting on future as a reference .