金门东南海域中强地震活动区的地震构造背景

金门东南海域是泉州—汕头地震带内的一个中强地震活动区。该海域是晚第三纪以来形成的断陷海湾 ,中强地震的发生与该海湾构造活动密切相关。对该海域断裂构造活动、地震活动、地球物理场的分析表明 ,中强地震多发生在 :F1 断裂以西及其与F1 3 ,F23 ,F4断裂的交汇处 ;海域局部莫霍面隆起西侧边缘 (热区中心西侧边缘 )地带 ;NE向重力梯度带向西扭曲处及正剩余布格异常Ⅰ区与Ⅲ区之间的地段 ,即深部高密度体周围的密度变异处

BACKGROUND OF SEISMOTECTONICS OF MAJOR EARTHQUAKES IN THE SEA AREA SOUTH-EAST OF JINMEN

The sea area south-east of Jinmen is active in major earthquakes located in the Quanzhou-Shantou seismic zone. This area is a faulting depressed gulf which developed in late Neogen. Occurrence of major events is associated with the structural activities of the gulf. In this paper, fractures and geophysical fields of this area are presented. Some geological and geophysical marks of seismotectonics are also suggested.