地质科技情报2017，Vol.36Issue(4)：222-227,249,7.DOI:10.19509/j.cnki.dzkq.2017.0429
南北地震带地磁加卸载响应比应用研究
Application of Geomagnetic Load-Unload Response Ratio Method in North-South Seismic Belt
摘要
Abstract
Electromagnetic properties change indielectric conductivity due to stress changes before the earthquake may cause the corresponding changes in phase and amplitude of regional vertical magnetic field diurnal variation curve,and hence geomagnetic load-unload response ratios an effective method for identification of abnormal amplitude.This paper calculates geomagnetic load-unload response ratios before 18 significant earthquakes in the north-south seismic belt,analyzes the geomagnetic load-unload response ration spatial distribution characteristics and the formation mechanism before earthquakes.The results indicate that:①In the exclusion of space weather,surrounding environment instrument and monitoring system and other factors,geomagnetic load-unload response ratio abnormal appearr before some strong earthquakes,accounting for 44.4 ％.②Geomagnetic load-unload response ratio threshold is affected by latitude,and in the condition of the same longitude,the greater the latitude,the lower the threshold.After repeated debugging and contrast,the calculation results show that the response ratio threshold of the north-south seismic belt in the northern section is 3,and that of south and southwest regions is 3.1.③In general,abnormal within 6 months after the occurrence of moderate earthquakes,the bigger the number of abnormal stations,the greater the magnitude of strong earthquakes.The epicenter is more likely to belocated near the threshold line.关键词
地磁加卸载响应比/日变幅/异常指标/地震预报/南北地震带Key words
geomagnetic load-unload response ratio/daily variation amplitude/abnormity index/earthquake prediction/north-south seismic belt分类
天文与地球科学引用本文复制引用
戴苗,冯志生,刘坚,李德前,魏贵春,申学林..南北地震带地磁加卸载响应比应用研究[J].地质科技情报,2017,36(4):222-227,249,7.基金项目
中国地震局地震监测、预测、科研三结合课题(161704) （161704）
中国地震局震情跟踪专项工作任务(2016010411) （2016010411）
