PRELIMINARY STUDY ON THE RELATIONSHIP BETWEEN THE M_S8.0 WENCHUAN EARTHQUAKE OF 2008 AND THE ANOMALIES OF EARTH RESISTIVITY OBSERVED AT QINGDAO SEISMIC STATION

Near-surface earth resistivity and underground water level anomalies were recorded at Qingdao seismic observatory of Shandon Province before and after the MS 8.0 Wenchuan Earthquake of May 12,2008.The observation data of the earth resistivity at the observatory revealed that the underground water level dropped and the resistivity increased.It is postulated that in the special tectonic setting as Qingdao observatory,the variation of stress and strain resulted in the change of water level beneath the station,leading to the variation of resistivity.The relationship between the variation of stress field and the change of earth resistivity before earthquake is analysed.