安徽省地震活动的地球物理场背景

安徽省是一个特殊的中强地震区,地震活动呈现华北、华南两大地震区的过渡特征。通过分析安徽省的重力异常及航磁异常资料,认为中强震往往发生于正负重力或航磁异常的交接部位;重力、航磁异常等值线梯级带上,莫霍面、磁性层上界面等深线的梯级带上;重力、航磁异常等值线的拐折部位,莫霍面、磁性层上界面等深浅的拐折部位。对这些结论提出了分析模式,并作了地震构造解释。最后,根据这些结论,预测了未来地震危险区。

GEOPHYSICAL FIELD BACKGROUND OF SEISMICITY IN ANHUI PROVINCE

Anhui province is a special moderate seismic region which has transitive characteristic between North China and South China seismic regions. Analysing data of gravity and aeromagnetic anomalies, It is concluded that moderate earthquake frequently occurred in the cross positions of positive and negative gravity or aeromagnetic anomalies, and in the step zone and inflection position of gravity and aeromagnetic anomalous isolines, and bathymetric lines of upper boundary surface of magnetic layer and Moko discontiunity, Analytical model is provided for these conclusions, and seismic structural interpretation is made, Finally, according to these conclusions, future seismic risk zones are predicted.