野外观测和室内试验表明，地震孕育和发生过程中可能产生电磁信号。地震电磁现象在防震减灾中具有潜在的应用价值，已成为21世纪国内外地学研究热点之一。由于地震电磁信号较弱，通常混杂于空间场源信号及人文噪音中，不易在观测数据中提取出来。以2003年1月日本茨城县5.1级地震为例，探讨远场参考在超低频（ULF）地震地磁数据处理中的应用，进而检测震前局部磁场异常。在此基础上，讨论远场参考法的优势及可能存在的不足。分析结果表明，2003年1月日本茨城县5.1级地震发生前存在局部磁场异常，验证了远场参考方法的有效性，相关成果可为地震地磁数据处理提供有益参考。
Field observations and indoor experiments have shown that electromagnetic signals may be generated during the earthquake's preparation and occurrence. Because of the potential application value in earthquake prevention and disaster mitigation, seismo-magnetic phenomena have become one of the research hotpots of geoscience at home and abroad in the 21st century. However, because the seismo-magnetic signals are usually weak, it is difficult to identify them from upper-atmosphere signals and artificial noises. In this study, we took the M 5.1 earthquake in Ibaraki, Japan in January 2003 as an example, to explore the application of remote reference in ultralow frequency (ULF) seismo-magnetic data processing, and intended to detect local magnetic anomalies before earthquakes. We further discussed the advantages and disadvantages of remote reference method. The results showed that there were local magnetic field anomalies before the M 5.1 earthquake in Ibaraki, Japan in January 2003, verifying the effectiveness of remote reference method.
2019,40(5): 48-55 收稿日期：2019-10-09
DOI：10.3969/j.issn.1003-3246.2019.05.007
基金项目：广东省自然科学基金（项目编号：2018A0303130010）；中国地震科学试验场项目（项目编号：2019CSES0105）
作者简介：孙健维(1994-),男,南方科技大学科研助理,主要从事信号处理与数据分析研究工作
*通讯作者：韩鹏(1985-),男,南方科技大学地球与空间科学系助理教授,主要从事地震活动性分析、地震概率预测及地震电磁学研究工作。E-mail:hanp@sustech.edu.cn
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