Disturbance identification of electric field data observed by the CSES-01 satellite before earthquakes

作     者：Jianping HUANG Fuzhi ZHANG Zhong LI Xuhui SHEN Baiyi YANG Wenjing LI Zhima ZEREN Hengxin LU Qiao TAN 

作者机构：National Institute of Natural HazardsMinistry of Emergency ManagementBeijing 100085China Institute of Intelligent Emergency Information ProcessingInstitute of Disaster PreventionLangfang 065201China 

出 版 物：《Science China Earth Sciences》 (中国科学（地球科学英文版）)

年 卷 期：2023年第66卷第8期

页      面：1814-1824页

核心收录：

学科分类：070801[理学-固体地球物理学] 07[理学] 0708[理学-地球物理学] 

基　　金：supported by the National Natural Science Foundation of China (Grant No. 42104159) the APSCO Earthquake Project (Phase Ⅱ) ISSI-BJ International Team (Grant No. 2019-33) Dragon 5 Cooperation Proposal (Grant No. #59308) 

主　　题：The CSES-01 satellite Whistle Electric field C-value method Normalization 

摘      要：Numerous studies have confirmed that electromagnetic disturbances before earthquakes can be observed by *** this study,we use the C-value method that includes the acoustic whistle signature;pre-seismic ionospheric electromagnetic disturbance signals were acquired based on the CSES-01 satellite electric field data,and the maximum value of C in the earthquake preparation zones increased continuously from 2.0 three days before the earthquake and reached a maximum weight of 3.0 on the day of the earthquake,after the earthquake,it gradually decreased and recovered to about 2.0;its the C values fluctuated between-2 and 3,it is different from the C values range-2–12 of the previous seismic case study using the DEMETER satellite,which may be related to the orbital altitude and revisit period of the ***,the C values were normalized,and the time series analysis of the obtained θ values were done,and the results showed that:In the pregnant zone,the background variation of the disturbance amplitude θ is within 2σ,and the maximum disturbance amplitude of θ starts to increase gradually from the seventh period(one period of 5 days,i.e.,35–39 days before the earthquake),it reached 2σ by the fourth preseismic cycle(20–24 days before the earthquake),and then dropped sharply to about 1.5σ in the third pre-seismic cycle(15–19days before the earthquake),after two cycles of increase,the θ over the epicenter reached a maximum of 2.1σ at the time of the earthquake(combining the time of the earthquake and the satellite flight characteristics,the epicenter period is defined as January25-January 29,2020,and this defines the study time period line),and the θ decreases to within 2 times the standard range after the earthquake;The negative value of the disturbance amplitude θ in the central region of the pregnant seismic zone during the earthquake shows the transient energy release *** comparison,the θ values obtained by normalization based on the C-value method