Changes and mechanisms of apparent resistivity before earthquakes of MS6.0–6.9 on the Chinese mainland

China has been conducting fixed continuous apparent resistivity observations since 1967. Up to June 2022, 45 earthquakes with magnitudes of M S 6.0–6.9 have occurred within a range approximately 250 km from normal operating stations. Through literature investigation and data analysis, monitoring stations counted 61 short-medium-term anomalous changes (i.e., 44 decrease changes, 15 increase 2 perturbance changes) appearing before 39 these earthquakes. In this study, we utilize fault virtual dislocation model understand the relative deformations around epicenters The comparison results showed that 36 were in areas compression enhancement 9 dilatancy. rock petrophysical experiments cracked medium decreased water-bearing geomaterials during successive loading compressive stress, while increased stress unloading process. Moreover, anomalies consistent mechanism change under stress. These may be related seismogenic processes such is caused by deformation.