{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,23]],"date-time":"2026-03-23T13:46:15Z","timestamp":1774273575184,"version":"3.50.1"},"reference-count":57,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2020,6,1]],"date-time":"2020-06-01T00:00:00Z","timestamp":1590969600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Chieh-Hung Chen","award":["201804"],"award-info":[{"award-number":["201804"]}]},{"name":"Jann-Yenq Liu","award":["107-2119-M-008-018"],"award-info":[{"award-number":["107-2119-M-008-018"]}]},{"name":"Jann-Yenq Liu","award":["108-2119-M-008-001"],"award-info":[{"award-number":["108-2119-M-008-001"]}]},{"name":"Yan Feng","award":["41974073"],"award-info":[{"award-number":["41974073"]}]},{"name":"Aisa\u00b7Yisimayili","award":["2019010409"],"award-info":[{"award-number":["2019010409"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Changes in the underlying conductivity around hypocenters are generally considered one of the promising mechanisms of seismo-electromagnetic anomaly generation. Parkinson vectors are indicators of high-conductivity materials and were utilized to remotely monitor conductivity changes during the MW 6.5 Jiuzhaigou earthquake (103.82\u00b0E, 33.20\u00b0N) on 8 August 2017. Three-component geomagnetic data recorded in 2017 at nine magnetic stations with epicenter distances of 63\u2013770 km were utilized to compute the azimuths of the Parkinson vectors based on the magnetic transfer function. The monitoring and background distributions at each station were constructed by using the azimuths within a 15-day moving window and over the entire study period, respectively. The background distribution was subtracted from the monitoring distribution to mitigate the effects of underlying inhomogeneous electric conductivity structures. The differences obtained at nine stations were superimposed and the intersection of a seismo-conductivity anomaly was located about 70 km away from the epicenter about 17 days before the earthquake. The anomaly disappeared about 7 days before and remained insignificant after the earthquake. Analytical results suggested that the underlying conductivity close to the hypocenter changed before the Jiuzhaigou earthquake. These changes can be detected simultaneously by using multiple magnetometers located far from the epicenter. The disappearance of the seismo-conductivity anomaly after the earthquake sheds light on a promising candidate of the pre-earthquake anomalous phenomena.<\/jats:p>","DOI":"10.3390\/rs12111777","type":"journal-article","created":{"date-parts":[[2020,6,2]],"date-time":"2020-06-02T09:19:27Z","timestamp":1591089567000},"page":"1777","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Locating Seismo-Conductivity Anomaly before the 2017 MW 6.5 Jiuzhaigou Earthquake in China Using Far Magnetic Stations"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6538-2703","authenticated-orcid":false,"given":"Zhiqiang","family":"Mao","sequence":"first","affiliation":[{"name":"Institute of Geophysics and Geomatics, China University of Geosciences, Wuhan 430074, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5440-2142","authenticated-orcid":false,"given":"Chieh-Hung","family":"Chen","sequence":"additional","affiliation":[{"name":"Institute of Geophysics and Geomatics, China University of Geosciences, Wuhan 430074, China"},{"name":"State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan 430074, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Suqin","family":"Zhang","sequence":"additional","affiliation":[{"name":"Institute of Geophysics, China Earthquake Administration, Beijing 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Aisa","family":"Yisimayili","sequence":"additional","affiliation":[{"name":"Earthquake Agency of Xinjiang Uygur Autonomous Region, Urumqi 830011, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Huaizhong","family":"Yu","sequence":"additional","affiliation":[{"name":"China Earthquake Networks Center, Beijing 10004, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chen","family":"Yu","sequence":"additional","affiliation":[{"name":"China Earthquake Networks Center, Beijing 10004, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jann-Yenq","family":"Liu","sequence":"additional","affiliation":[{"name":"Graduate Institute of Space Science, National Central University, Taoyuan 32001, Taiwan"},{"name":"Center for Space and Remote Sensing Research, National Central University, Taoyuan 32001, Taiwan"},{"name":"Center for Astronautical Physics and Engineering, National Central University, Taoyuan 32001, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,1]]},"reference":[{"key":"ref_1","first-page":"350","article-title":"SMART analysis of geomagnetic data observed in Taiwan","volume":"34","author":"Chen","year":"2009","journal-title":"Phys. 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