Basement structures and basement interfaces are obtained by finite-difference and time-term methods using Pg-wave data from two deep seismic sounding (DSS) profiles in the Artush-Jiashi strong earthquake area. The geo...Basement structures and basement interfaces are obtained by finite-difference and time-term methods using Pg-wave data from two deep seismic sounding (DSS) profiles in the Artush-Jiashi strong earthquake area. The geological units differ considerably in basement depth. The basement structures of contact zones between two geological units also vary obviously, which marks the existence of boundary faults. Finally, we make a remark upon the relationship between characteristics of basement structures and seismicity in the Artush meizoseismal area and the Jiashi earthquake swarm area.展开更多
The study found that strong magnetic anomalies repeatedly took place before big earthquakes. Based on geomagnetic record analysis results,we discussed a possible pattern of the magnetic anomalies prior to earthquake. ...The study found that strong magnetic anomalies repeatedly took place before big earthquakes. Based on geomagnetic record analysis results,we discussed a possible pattern of the magnetic anomalies prior to earthquake. In meizoseismal area or epicenter,in a time period of 36 h to about 10 min before earthquake,the exceptional big geomagnetic change increases with the magnitude of earthquake. We calculated that,in a place of 1 km from the epicenter,the magnetic anomaly before destructive earthquakes of Ms 6～9 can reach to 102～104 nT(the magnitude of earth magnetic field is 104 nT) ,rather than the magnitude of 10 nT from seismomagnetic effect theories since 1960s. From this we speculated the abnormal magnetic ULF near epicenter before earthquake seems to be an "intermittent magnetic eruption". Accordingly,we proposed that geomagnetic induction earthquake alarm can be a new pre-warning method to surmount hardship in solving the puzzledom of earthquake imminent prediction.展开更多
基金State Key Basic Research Development and Programming Project Mechanism and Prediction of Strong Continental Earthquake (G1998040702) and Joint Seismological Science Foundation of China (198062). Contribution No. GPB200109 Research Center of Exploration
文摘Basement structures and basement interfaces are obtained by finite-difference and time-term methods using Pg-wave data from two deep seismic sounding (DSS) profiles in the Artush-Jiashi strong earthquake area. The geological units differ considerably in basement depth. The basement structures of contact zones between two geological units also vary obviously, which marks the existence of boundary faults. Finally, we make a remark upon the relationship between characteristics of basement structures and seismicity in the Artush meizoseismal area and the Jiashi earthquake swarm area.
文摘The study found that strong magnetic anomalies repeatedly took place before big earthquakes. Based on geomagnetic record analysis results,we discussed a possible pattern of the magnetic anomalies prior to earthquake. In meizoseismal area or epicenter,in a time period of 36 h to about 10 min before earthquake,the exceptional big geomagnetic change increases with the magnitude of earthquake. We calculated that,in a place of 1 km from the epicenter,the magnetic anomaly before destructive earthquakes of Ms 6～9 can reach to 102～104 nT(the magnitude of earth magnetic field is 104 nT) ,rather than the magnitude of 10 nT from seismomagnetic effect theories since 1960s. From this we speculated the abnormal magnetic ULF near epicenter before earthquake seems to be an "intermittent magnetic eruption". Accordingly,we proposed that geomagnetic induction earthquake alarm can be a new pre-warning method to surmount hardship in solving the puzzledom of earthquake imminent prediction.
