On the relation of the imminent sudden change in earth resistivity to the active fault and earthquake generating stress field

Abstract

In this paper, the relations of the changes of earth resistivity (ρ) s recorded at 100 geoelectrical stations in 31 earthquakes occurred in the continent of China, to the active faults (active abyssal faults or badly active faults near the focal zone) and the causative stress fields are discussed and the following conclusions are obtained: (1) On the condition that a station is near the active fault and in the direction of the causative stress (DCS) of an earthquake (EQ), the immediate variation ofρ s to the earthquake (called “immediate variation” for short) could be recorded generally at the station. (2) The active fault which lies between a station and the epicenter of an earthquake seems to play a role in “obstructing” the recording of the imminent variation when the strike of the fault is close to the DCS of the earthquake. When that is parrallel with the DCS the “obstructing” function of the fault is strongest; when normal with the DCS, weakest.