2023年积石山MW6.0地震前电离层TEC与声重波耦合现象
Phenomenon of Ionospheric TEC Coupled with Acoustic-gravity Waves Preceding Jishishan MW6.0 Earthquake in 2023
刘红 1张学民 1杨娜1
作者信息
- 1. 中国地震局地震预测研究所,北京 100036
- 折叠
摘要
电离层异常是地震短临预报过程的重要参考,目前已经积累了丰富的研究成果.与地震电离层异常形成机制相关的LAI耦合模型也得到了发展,其中声重波途径受到了广泛关注.本研究基于中国大陆构造环境监测网络(CMONOC)GNSS观测站提取到的北斗导航卫星系统(BDS)电离层总电子含量(TEC)数据,通过小波变换等分析方法,对2023年12月18日甘肃积石山MW6.0地震前14 h至震后2 h内TEC扰动的频谱特征和时空变化进行了探究,并与背景扰动信号和外源信号进行了对比.结果表明,临震前声重波扰动信号主要表现为向外辐散的弧状结构,反向定位结果表明该扰动弧源点接近震源位置.该扰动信号同时还受到了MSTIDs背景信号的载波作用和两个外源信号的干扰.最后,讨论了地表声重波信号的激发起源机制,指出地震孕育过程与声重波的联系仍需进一步验证和探究.
Abstract
Ionospheric precursors are crucial indicators for short-term earthquake prepara-tion,and abundant observations of them have been accumulated.Meanwhile,develop-ments concerning the formation mechanisms of seismology ionospheric anomalies have led to increasing interest in the LAI coupling process,in which the AGW-agent hypothesis has been intensively discussed.Based on the BDS TEC data collected by CMONOC GNSS sta-tions,this paper explores the spectral characteristics and spatial-temporal variations of the TEC perturbations from 14 hours before to 2 hours after the Jishishan MW6.0 earthquake on December 18,2023,in Gansu Province,China.According to the results,the pre-earthquake AGW-induced perturbation originated from points close to the epicenter and then dispersed outward as an arc-like structure.In addition,the background signal MSTIDs played the role of a carrier in the propagation of the perturbation,while the other two external signals exerted an interference effect on it.Finally,two promising candidates for the excitation and origination of the surface AGW signal are reviewed.Nevertheless,the connection between earthquake preparation and AGW signals needs further validation and investigation.
关键词
2023年积石山MW6.0地震/BDS/TEC/声重波途径/地震电离层异常Key words
The 2023 Jishishan MW6.0 earthquake/BDS TEC/Acoustic-gravity wave/Seismo-ionospheric anomaly引用本文复制引用
出版年
2024
NETL
NSTL
万方数据