高频BDS/GPS融合PPP确定2021年玛多M_(W)7.4地震三要素  

Determination of Three Parameters of the 2021 Maduo M_(W)7.4 Earthquake Using High-rate BDS/GPS

作　　者：张怀 聂兆生[1] 刘刚[1] 熊维[1] 倪乙鹏 黄军 ZHANG Huai;NIE Zhaosheng;LIU Gang;XIONG Wei;NI Yipeng;HUANG Jun(Institute of Seismology,China Earthquake Administration,Wuhan 430071,Hubei,China;Helongjiang Provincial Gedogy and Mineral Resources Test and Application Inshitute,Harbin 150036,Heilongjiang,China)

机构地区：[1]中国地震局地震研究所,湖北武汉430071 [2]黑龙江省地质矿产实验测试研究中心,黑龙江哈尔滨150036

出　　处：《地震研究》2023年第2期216-225,共10页Journal of Seismological Research

基　　金：国家自然科学基金项目(42074015,41874018);中国地震局星火计划攻关项目(XH20038);科技部研发专项(2018YFE0206100)。

摘　　要：基于GREAT程序,利用GPS和BDS/GPS融合PPP(精密单点定位)获取了2021年玛多M_(W)7.4地震10个高频GNSS测站的地震时间序列,并通过历元间差分法获得了震前30 min的速度时间序列。分析发现,相对于GPS,BDS/GPS速度时间序列在东西、北南、垂直3个方向的精度分别提高了14.8%、15.2%和3.5%。利用STA/LTA(短时窗平均/长时窗平均)方法,从各测站GPS和BDS/GPS时间序列中提取了地震波初至时刻;利用2种时间序列计算得到的震中位置和发震时刻分别为(34.6°N,98.54°E),18:04:28.8和(34.63°N,98.51°E),18:04:29.2(UTC);利用GPS和BDS/GPS峰值地面位移,根据经验公式反演了玛多地震震级分别为M_(W)7.34和M_(W)7.36,BDS/GPS震级与GCMT公布的结果(M_(W)7.4)更为接近。结果表明:BDS/GPS融合PPP解算可提高时间序列稳定性并降低噪声,更真实地描述震时地表位移变化,从而提高震级解算准确性,更好地为地震预警、地震应急救援等工作提供数据支持。The seismic time series of 10 high-rate GNSS stations during the 2021 Maduo M_(W)7.4 earthquake were acquired using GPS and BDS/GPS fusion PPP based on the GREAT program,and the velocity time series 30 minutes before the earthquake were obtained based on the variometric approach.The analysis found that the BDS/GPS relative to GPS velocity RMS values in the EW,NS and UP orientation can be improved by 14.8%,15.2%and 3.5%respectively.The seismic wave’s first arrival-time was extracted from the BDS/GPS time series of each station using the STA/LTA method,the location of the epicenter of the Maduo earthquake was(34.63°N,98.51°E),and the earthquake’s original time was 18:04:29(UTC),calculated from the time of first arrival of seismic waves at each station.This article refers to the time of the Maduo earthquake,using the Coordinated Universal Time.The epicenter of the Maduo earthquake calculated by GPS time series is(34.6°N,98.54°E),and the original time is 18:04:28.8.Using GPS and BDS/GPS peak ground displacement,the Maduo earthquake magnitude was inverted according to the empirical formula,and the obtained magnitudes were M_(W)7.36 and M_(W)7.34,respectively.The BDS/GPS magnitude was closer to the result published by GCMT.The results show that the BDS/GPS fusion PPP solution can improve the stability of time series and reduce noise,which can more realistically describe the surface displacement changes during the earthquake,thus improving the accuracy of the magnitude solution and providing better data support for earthquake early warning and post-earthquake rescue.

关 键 词：BDS/GPS 精密单点定位 地壳形变监测 地震三要素 玛多地震 

分 类 号：P315.725[天文地球—地震学]