Journal of Geodesy and Geoinformation Science ›› 2021, Vol. 4 ›› Issue (1): 116-123.doi: 10.11947/j.JGGS.2021.0114

• Special Issue • Previous Articles     Next Articles

Earthquake Electromagnetic Precursor Anomalies Detected by a New Ground-based Observation Network

Bing HAN1(),Guoze ZHAO1(),Lifeng WANG1,Ji TANG1,Yaxin BI2,Yan ZHAN1,Xiaobin CHEN1,Qibin XIAO1,Jihong ZHANG3   

  1. 1. The State Key Laboratory of Earthquake Dynamics. Institute of Geology, China Earthquake Administration, Beijing 100029, China
    2. Computer Science Research Institute, Faculty of Computing and Engineering, University of Ulster, Belfast BT37 0QB, U.K.
    3. Shandong Earthquake Administration, Jinan 250014, China
  • Received:2020-10-10 Accepted:2020-12-25 Online:2021-03-20 Published:2021-04-06
  • Contact: Guoze ZHAO E-mail:zddhb@163.com;zhaogz@ies.ac.cn
  • About author:Han Bing (1988-), female, research assistant, majors in MT data processing and analyzing. E-mail: zddhb@163.com
  • Supported by:
    National Development and Reform Committee of China(15212Z0000001);National Science Foundation of China(41374077)

Abstract:

It is a debated topic if there are any observable precursor anomalies prior to the earthquake (EQ hereafter) and if the stronger EQ can be successfully predicted. During last few decades quite a lot of observable electromagnetic (EM) precursors were published by using techniques equipped in either satellites or on ground-based stations. But there are only a few cases that the short-term precursor anomalies of EM field before earthquakes were observed by using alternate EM fields on ground. This paper will present a new EM observation network built in recent years and show a new finding of EM field with the variation of a one-year cycle observed using the network. As an example, the short-term precursor anomalies of apparent resistivity before the Yangbi EQ (Ms 5.1) occurred on March 27, 2017 in Yunnan Province will be studied. The observed anomalous phenomena indicate that the anomaly before the EQ can be captured only if reasonable effective methods including sophisticated analytical techniques are used, and it is believed that continuously observed data on the fixed observation network for a long time is an effective means for studying anomalies that appeared before earthquakes. This network can also play an important role in studying the EM environment from space.

Key words: electromagnetic observation network; natural EM phenomena; precursor anomaly; apparent resistivity; space EM environment