The occurrence and development of earthquakes can cause abnormal changes in the lithospheric magnetic field.High-precision geomagnetic observations on both sides of the Dingri M6.8 epicenter revealed a−120 nT differen...The occurrence and development of earthquakes can cause abnormal changes in the lithospheric magnetic field.High-precision geomagnetic observations on both sides of the Dingri M6.8 epicenter revealed a−120 nT difference in the lithospheric magnetic field between the west and east sides,reflecting the local difference characteristics of the properties of the crustal medium around the epicenter.From 2018 to 2020,the annual variation of the magnetic field changed from−2.2 nT to+3.9 nT,which may be the precursor anomaly of the Dingri M5.9 earthquake in 2020.Calculations show that in the coseismic magnetic field variation of the M6.8 earthquake,the piezomagnetic effect is small while the electrokinetic effect is large,so the precursor anomaly of the M5.9 earthquake may be related to the electrokinetic effect produced by underground fluid migration.展开更多
基金supported by Hebei Earthquake Science and Technology Spark Program Project(Grant No.DZ2024112200008).
文摘The occurrence and development of earthquakes can cause abnormal changes in the lithospheric magnetic field.High-precision geomagnetic observations on both sides of the Dingri M6.8 epicenter revealed a−120 nT difference in the lithospheric magnetic field between the west and east sides,reflecting the local difference characteristics of the properties of the crustal medium around the epicenter.From 2018 to 2020,the annual variation of the magnetic field changed from−2.2 nT to+3.9 nT,which may be the precursor anomaly of the Dingri M5.9 earthquake in 2020.Calculations show that in the coseismic magnetic field variation of the M6.8 earthquake,the piezomagnetic effect is small while the electrokinetic effect is large,so the precursor anomaly of the M5.9 earthquake may be related to the electrokinetic effect produced by underground fluid migration.
