大震复发周期具有区域性的差异。在地震复发周期很长的地区,仅仅根据少量地震史料进行烈度区划具有明显的局限性。在有些低烈度区“意外”地发生毁灭性大震就属于这种情况。为了弥补历史地震记录资料的不足,古地震遗迹的研究就具有重要意义。 天津滨海平原成陆甚晚,人类定居及文化发展较迟。从目前已掌握的史料看,发生在 There are regional differences in the recurrence cycle of large earthquakes. In regions with long earthquake recurrence intervals, the intensity division based on only a small amount of historical data has obvious limitations. This is the case with the “unexpected” devastating earthquake in some areas of low intensity. In order to make up for the lack of historical records of seismic data, the study of ancient earthquakes is of great significance. Tianjin coastal plains into the land is late, human settlements and cultural development later. From the current grasp of historical data, occurred in