{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T15:46:16Z","timestamp":1783007176533,"version":"3.54.5"},"reference-count":28,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2022,6,5]],"date-time":"2022-06-05T00:00:00Z","timestamp":1654387200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"APSCO","award":["the APSCO Earthquake Research Project Phase II, #59308"],"award-info":[{"award-number":["the APSCO Earthquake Research Project Phase II, #59308"]}]},{"name":"APSCO","award":["2018YFC1503506"],"award-info":[{"award-number":["2018YFC1503506"]}]},{"name":"National Key R&amp;D Program of China","award":["the APSCO Earthquake Research Project Phase II, #59308"],"award-info":[{"award-number":["the APSCO Earthquake Research Project Phase II, #59308"]}]},{"name":"National Key R&amp;D Program of China","award":["2018YFC1503506"],"award-info":[{"award-number":["2018YFC1503506"]}]},{"name":"Joint Innovation Center of Space Science (Aerospace Shanghai)","award":["the APSCO Earthquake Research Project Phase II, #59308"],"award-info":[{"award-number":["the APSCO Earthquake Research Project Phase II, #59308"]}]},{"name":"Joint Innovation Center of Space Science (Aerospace Shanghai)","award":["2018YFC1503506"],"award-info":[{"award-number":["2018YFC1503506"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Studies on magnetic disturbances in ultralow frequency ranges related to earthquakes observed by satellites are still limited. Based on Swarm satellites, this paper proposes a new analysis method to investigate pre-earthquake magnetic disturbances by excluding some known non-earthquake magnetic effects that are not confined to those caused by intense geomagnetic activity. This method is demonstrated by two earthquake cases. One is an interplate earthquake, and the other is an intraplate earthquake. Magnetic disturbances around these two earthquakes are associated with solar wind and geomagnetic activity indices, electron density and field-aligned currents. Magnetic disturbances several days before earthquakes do not show clear relations with the already known magnetic effects. These nightside disturbances (LT~17\/18, ~02), possibly related to earthquakes observed by Swarm satellites, oscillate in the transverse magnetic field below 2 Hz, propagate along the background magnetic field and are mostly linearly polarized.<\/jats:p>","DOI":"10.3390\/rs14112709","type":"journal-article","created":{"date-parts":[[2022,6,5]],"date-time":"2022-06-05T10:47:11Z","timestamp":1654426031000},"page":"2709","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["A New Analysis Method for Magnetic Disturbances Possibly Related to Earthquakes Observed by Satellites"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6141-0378","authenticated-orcid":false,"given":"Xin-Yan","family":"Ouyang","sequence":"first","affiliation":[{"name":"Institute of Earthquake Forecasting, China Earthquake Administration, Beijing 100036, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yong-Fu","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Earth and Space Sciences, Peking University, Beijing 100871, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xue-Min","family":"Zhang","sequence":"additional","affiliation":[{"name":"Institute of Earthquake Forecasting, China Earthquake Administration, Beijing 100036, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ya-Lu","family":"Wang","sequence":"additional","affiliation":[{"name":"Institute of Earthquake Forecasting, China Earthquake Administration, Beijing 100036, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ying-Yan","family":"Wu","sequence":"additional","affiliation":[{"name":"Institute of Earthquake Forecasting, China Earthquake Administration, Beijing 100036, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Zhao, S., Shen, X., Liao, L., Zhima, Z., Zhou, C., Wang, Z., Cui, J., and Lu, H. (2020). Investigation of Precursors in VLF Subionospheric Signals Related to Strong Earthquakes (M > 7) in Western China and Possible Explanations. Remote Sens., 12.","DOI":"10.3390\/rs12213563"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Zhang, X., Wang, Y., Boudjada, M.Y., Liu, J., Magnes, W., Zhou, Y., and Du, X. (2020). Multi-Experiment Observations of Ionospheric Disturbances as Precursory Effects of the Indonesian Ms6.9 Earthquake on 5 August 2018. Remote Sens., 12.","DOI":"10.3390\/rs12244050"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"360","DOI":"10.1016\/j.pce.2008.04.005","article-title":"A new ULF wave analysis for Seismo-Electromagnetics using CPMN\/MAGDAS data","volume":"34","author":"Yumoto","year":"2009","journal-title":"Phys. Chem. Earth Parts A B C"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1465","DOI":"10.1029\/GL017i009p01465","article-title":"Low-frequency magnetic field measurements near the epicenter of the Ms 7.1 Loma Prieta earthquake","volume":"17","author":"Bernardi","year":"1990","journal-title":"Geophys. Res. Lett."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"241","DOI":"10.1029\/95GL02863","article-title":"Results of ultra-low-frequency magnetic field measurements during the Guam Earthquake of 8 August 1993","volume":"23","author":"Hayakawa","year":"1996","journal-title":"Geophys. Res. Lett."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"2825","DOI":"10.5194\/angeo-26-2825-2008","article-title":"The possible statistical relation of Pc1 pulsations to Earthquake occurrence at low latitudes","volume":"26","author":"Bortnik","year":"2008","journal-title":"Ann. Geophys."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"4998","DOI":"10.1002\/2014JA019789","article-title":"Statistical analysis of ULF seismomagnetic phenomena at Kakioka, Japan, during 2001\u20132010","volume":"119","author":"Han","year":"2014","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"293","DOI":"10.1007\/s10712-012-9215-x","article-title":"Investigation of ULF Seismo-Magnetic Phenomena in Kanto, Japan During 2000\u20132010: Case Studies and Statistical Studies","volume":"34","author":"Hattori","year":"2013","journal-title":"Surv. Geophys."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1691","DOI":"10.1029\/94JA02524","article-title":"Penetration characteristics of electromagnetic emissions from an underground seismic source into the atmosphere, ionosphere, and magnetosphere","volume":"100","author":"Molchanov","year":"1995","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1091","DOI":"10.5194\/nhess-11-1091-2011","article-title":"Enhanced ULF radiation observed by DEMETER two months around the strong 2010 Haiti earthquake","volume":"11","author":"Athanasiou","year":"2011","journal-title":"Nat. Hazards Earth Syst. Sci."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1597","DOI":"10.5194\/angeo-31-1597-2013","article-title":"Changes in the ultra-low frequency wave field during the precursor phase to the Sichuan earthquake: DEMETER observations","volume":"31","author":"Walker","year":"2013","journal-title":"Ann. Geophys."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"85","DOI":"10.1016\/j.asr.2012.03.018","article-title":"Ground-based and satellite DC-ULF electric field anomalies around Wenchuan M8.0 earthquake","volume":"50","author":"Zhang","year":"2012","journal-title":"Adv. Space Res."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1016\/j.epsl.2016.12.037","article-title":"Potential earthquake precursory pattern from space: The 2015 Nepal event as seen by magnetic Swarm satellites","volume":"461","author":"Balasis","year":"2017","journal-title":"Earth Planet. Sci. Lett."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"e2020JA028396","DOI":"10.1029\/2020JA028396","article-title":"ULF Wave Activity Observed in the Nighttime Ionosphere Above and Some Hours Before Strong Earthquakes","volume":"125","author":"Ouyang","year":"2020","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"456","DOI":"10.1016\/j.pss.2005.10.016","article-title":"ICE, the electric field experiment on DEMETER","volume":"54","author":"Berthelier","year":"2006","journal-title":"Planet. Space Sci."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1627","DOI":"10.1021\/ac60214a047","article-title":"Smoothing and Differentiation of Data by Simplified Least Squares Procedures","volume":"36","author":"Savitzky","year":"1964","journal-title":"Anal. Chem."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1029\/2018GL080693","article-title":"Large-Scale Ducting of Pc1 Pulsations Observed by Swarm Satellites and Multiple Ground Networks","volume":"45","author":"Kim","year":"2018","journal-title":"Geophys. Res. Lett."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"5551","DOI":"10.1029\/JA077i028p05551","article-title":"Use of the three-dimensional covariance matrix in analyzing the polarization properties of plane waves","volume":"77","author":"Means","year":"1972","journal-title":"J. Geophys. Res."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"A04204","DOI":"10.1029\/2006JA011900","article-title":"An automatic wave detection algorithm applied to Pc1 pulsations","volume":"112","author":"Bortnik","year":"2007","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1025","DOI":"10.1007\/BF00876083","article-title":"Estimation of the size of earthquake preparation zones","volume":"117","author":"Dobrovolsky","year":"1979","journal-title":"Pure Appl. Geophys."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"3069","DOI":"10.1002\/2015GL063662","article-title":"The interhemispheric and F region dynamo currents revisited with the Swarm constellation","volume":"42","author":"Kervalishvili","year":"2015","journal-title":"Geophys. Res. Lett."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"9","DOI":"10.5047\/eps.2013.09.006","article-title":"Determining field-aligned currents with the Swarm constellation mission","volume":"65","author":"Ritter","year":"2013","journal-title":"Earth Planets Space"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"A02304","DOI":"10.1029\/2005JA011184","article-title":"Magnetic signatures of equatorial spread F as observed by the CHAMP satellite","volume":"111","author":"Stolle","year":"2006","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"5884","DOI":"10.1002\/2017GL073385","article-title":"On the direction of the Poynting flux associated with equatorial plasma depletions as derived from Swarm","volume":"44","author":"Stolle","year":"2017","journal-title":"Geophys. Res. Lett."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"5936","DOI":"10.1029\/2019JA026700","article-title":"On the Balance Between Plasma and Magnetic Pressure Across Equatorial Plasma Depletions","volume":"124","author":"Stolle","year":"2019","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"495","DOI":"10.1007\/s11214-016-0295-7","article-title":"Low and Midlatitude Ionospheric Plasma Density Irregularities and Their Effects on Geomagnetic Field","volume":"206","author":"Yokoyama","year":"2017","journal-title":"Space Sci Rev."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"A03307","DOI":"10.1029\/2008JA013792","article-title":"Magnetic signatures of medium-scale traveling ionospheric disturbances as observed by CHAMP","volume":"114","author":"Park","year":"2009","journal-title":"J. Geophys. Res. Space Phys."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"10794","DOI":"10.1029\/2019JA027523","article-title":"Comprehensive Analysis of the Magnetic Signatures of Small-Scale Traveling Ionospheric Disturbances, as Observed by Swarm","volume":"124","author":"Yin","year":"2019","journal-title":"J. Geophys. Res. Space Phys."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/14\/11\/2709\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T23:24:40Z","timestamp":1760138680000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/14\/11\/2709"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,6,5]]},"references-count":28,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2022,6]]}},"alternative-id":["rs14112709"],"URL":"https:\/\/doi.org\/10.3390\/rs14112709","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,6,5]]}}}