【摘要】 作者认为从分析历史地震及现代地震出发可发现苏皖地区地震的时空分布有网络特征。其发展有单向迁移、双向扩展及跳跃三种方式。若把时间尺度放长,三种方式均能体现在同一网络线上。网络的发展是不均匀的,就苏皖地区而言,NE向比NW向释放的地震能量大,但整体上两者的地震能量是向东部海域衰减的。自有历史记载以来,地震活动频度有由西向东迁移的趋势,现代地震主要集中在该区的东部地区。在时间上,地震活动可明显地分为四个地震活跃期及三个平静期。后两个地震活跃期在时间上与华北的第三、第四活跃期有相同的数量级,但震级却差一到二级。这说明苏皖地区的地壳活动程度低于华北而又高于华南,它是由现代活动大陆地壳向稳定大陆地壳过渡的过渡带。在这种构造背景下,苏皖地区的地震形成纬向成带,斜向成网的格局。 本文还根据网络围空方法并结合区域构造特点,推测未来一、二十年内有可能发生中小地震(4～6级)的潜在发震点。更多还原

【Abstract】 Based on the analysis of the historical and recent earthquake records in Jiangsu and Anhui area, the author suggested that the earthquakes occurred mainly along NE and NW trending. The two direction lines formed earthquake frameworks. The epicenters, for the most part, located in where the NE trending was crossed with that of NW. The seismic energy released along the NE trending was greater than that of NW trending. It implied that the NW trending would be more activated. If the places where the NE trending was intersected with the NW trending had not yet unlocked by earthquakes, they were seismic gaps and probably the potential epicenters of the next earthquakes. The frequency of seismic activity in this area had migrated eastwards since the beginning of the historical recording, but the released energy was decreased eastwards. Throughout the historical time, the earthquakes concentrated in four active periods which had been separated by three inactive periods in which there were hardly earthquakes. Each active period could be further divided into shorter periods called seismic episodes. We can prefigure the earthquake trending by comparing the present seismic episode with the preceded ones.Considering the tectonic setting of this area, the author gave a tentative explanation for the seismic frameworks. The development of seismic frameworks was discussed. Three developing patterns of seismic frameworks were recognized. They werer one-way migrating,two-way spreading and jump-leaping patterns. The potential places of earthquakes were given based on the hypothesis of space-filling earthquakes.更多还原