四川及周边地区TEC异常与印度尼西亚地震关联性研究

The Correlation between TEC Anomaly in Sichuan and Surronding Region and Indonesia Earthquakes

使用中国地壳运动观测网络和美国喷气动力实验室的GPS TEC数据,通过滑动四分位法,对2019年8月2日印度尼西亚苏门答腊岛南部海域6.8级地震进行分析,研究印度尼西亚地震与四川及周边地区TEC异常的关联性。基于对四川及周边地区以及全球TEC的监测,我们发现在2019年7月25日(震前一周),印度尼西亚地震震源区及其北半球的磁共轭区域曾发生不同程度的TEC异常扰动现象。结合2011-2019年四川及周边地区GPS TEC数据与印尼6.0级以上地震目录统计分析发现,大部分印尼6.0级以上地震会在四川及周边地区出现TEC异常扰动现象。在时间上,异常集中在震前10 d至震后4 d的范围内,主要发生在地方时6:00-11:00,在7:00(LT)和10:00(LT)两个时刻形成两个峰值,而在夜间出现相关的异常最少;在空间上,在四川地区存在TEC异常的印尼强震集中在印尼西侧,印尼西侧与四川地区TEC异常表现出良好的关联性,且TEC异常扰动现象面积约为32×10^(4) km^(2),异常面积巨大,易于监测。研究结果表明,四川及周边地区TEC异常与印尼6.0级以上强震具有很好的时空关联性,结合全球TEC异常分布可以对印尼地区地震监测发挥重要作用。

Using the GPS TEC data from China Crustal Movement Observation Network and Jet Populsion Laboratry,this paper analyzes the MS6.8 earthquake in the south of Sumatra island,Indonesia on August 2,2019 by the sliding quartile method and studies the correlation between the Indonesia earthquake and the TEC anomaly in Sichuan and surrounding region.Through the monitoring of TEC in Sichuan and surronding region and the world,we can clearly found that on July 25,2019(one week before the earthquake),TEC anomaly occurred in the epicenter region of Indonesia earthquake and the magnetic conjugate region of the northern hemisphere.Combined with the statistical analysis from 2011 to 2019,it was found that most earthquakes of MS6.0 and above in Indonesia induced TEC anomalies in the Sichuan and surronding region.In terms of time,the anomalies are concentrated in the 10 days before the earthquake to 4 days after the earthquake,and mainly occur from 6:00 to 11:00(LT),where two peaks are formed at 7:00 and 10:00,with the less anomalies in the nights;spatially,the strong earthquakes in Indonesia with TEC anomaly in Sichuan area are concentrated in the west of Indonesia,which shows good correlation with TEC anomaly in Sichuan region,the TEC anomalies in the Sichuan region caused by strong Indonesian earthquakes is about 32×10^(4) km^(2),being huge and easy to monitor.In summary,The TEC anomalies in Sichuan and surrounding region has a significant spatial-temporal correlation with strong earthquakes in Indonesia.Combined with the global TEC anomaly mapping,TEC anomaly analysis in Sichuan region can play an important role for monitoring earthquakes in Indonesia.