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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。
The author believes that from the analysis of historical earthquakes and modern earthquakes, we can find that the spatial and temporal distribution of earthquakes in Jiangsu and Anhui has network characteristics. The development of one-way migration, two-way expansion and jump in three ways. If the time scale, three ways can be reflected in the same network line. Network development is uneven, in terms of Jiangsu and Anhui provinces, NE to NW seismic energy than to release large, but both the overall seismic energy is attenuated to the eastern waters. Since the historical records, the frequency of seismic activity tends to migrate from west to east. Modern earthquakes are mainly concentrated in the eastern part of the area. In time, the seismic activity can be clearly divided into four seismic active periods and three quiet periods. The last two active earthquakes have the same order of magnitude as the third and the fourth active periods of North China in time, but the magnitude of the earthquakes is one to two worse. This shows that the crustal activity in the Jiangsu-Anhui area is lower than that in North China and higher than that in South China. It is a transition zone from the modern continental crust to the stable continental crust. Under this tectonic setting, the earthquakes in Jiangsu and Anhui regions formed zonal belt and oblique net formation. This article also surrounded by empty method according to the network in conjunction with regional structural features, suggesting that small earthquakes can occur (4 to 6) of a potential causative point next twenty years.