2020年新疆于田6.4级地震前电离层扰动现象分析  

The Seismo-ionospheric Disturbances before the 2020 Yutian M_(S)6.4 Earthquake

作　　者：张学民[1] 刘静[1] 熊攀[1] 周煜林 ZHANG Xue-min;LIU Jing;XIONG Pan;ZHOU Yu-lin(Institute of Eart hquake For ecasting,China Earthquake Administration,Beijng 100036,China)

机构地区：[1]中国地震局地震预测研究所,北京100036

出　　处：《地震》2021年第2期145-157,共13页Earthquake

基　　金：国家重点研发计划课题(2018YFC1503506);国家自然基金项目(41674156);国际空间科学学会项目(ISSI-BJ,IT2019-33);Dragon-5国际合作项目(#58892,#59308)。

摘　　要：基于中国区域GPS反演TEC、JPLTEC mapping、张衡一号卫星探测等离子体参量数据,着重分析了2020年6月26日新疆于田6.4级地震前的电离层异常现象,结合之前于田发生的两次7级以上地震,研究认为于田地震前异常集中出现在震前一周内,以上升异常为主,异常有明显的局地效应,部分异常在磁共轭区有同步效应。多参量综合分析增强了异常的判识能力,并提高了异常的可靠性。太阳及空间磁扰活动对电离层地震判识有较大影响,会极大增加全球异常频次,但日食现象引起的TEC扰动与地震电离层异常有明显差异,较易区分,弱磁扰活动下的地震电离层异常判识能力有待加强。Based on the multi data of TEC inversed from GPS observations in Chinese mainland,TEC mapping published by JPL,plasma parameters from Zhangheng-1 satellite,the ionospheric perturbations were analyzed around Yutian M_(S)6.4 earthquake on 26 June 2020,in Xinjiang Uygur Autonomous Region.Combined with the results for two earthquakes in this region with magnitude larger than 7.0,it is found that the seismo-ionospheric disturbances in Yutian region concentrated 1 week before,mainly with increasing features and local effects,in which some showed simultaneous anomaly at its conjugate region.The comprehensive multi data analysis can improve the distinguishing capability for earthquake-related anomalies,and enhance their reliability.The solar activity and space magnetic disturbances will cause high frequent anomaly occurrence in the global maps,and influence heavily for abstracting the seismo-ionospheric signals.But a case study for solar eclipse on 21 June 2020 induced decreasing TEC anomalies,which is totally different with those related to Yutian earthquake,whatever in region or abnormal state.How to distinguish the seismo-ionospheric perturbations under weak magnetic disturbance condition still need further investigation.

关 键 词：2020年于田6.4级地震 地震电离层扰动 GPSTEC JPLTECmapping 张衡一号卫星 

分 类 号：P315.7[天文地球—地震学]