Abstract: We have studied the method of dynamic pattern generation,the characteristics of time space evolution of sliding variation extent of groundwater level and its mode of formation and evloution before and after the Tangshan earthquake of 1976. The results show that the positive and negative areas and anomaly characteristic area of the sliding variation extent of groundwater level present the distinct features of stage and regularity before and after the Tangshan earthquake. The negative area has the feature of“contraction-extention-quick extention-occurrence of earthquake”. The anomaly characteristic area displays the feature of“migation form periphery to epicentre-extention-stabilization-earthquake occurring-disappear”. The sliding variation extent of groundwater level in the anomaly characteristic area presents the feature of“increase-discrease-earthquake occurring-quick discrease”. We have also analyzed the dynamic pattern of sliding variation extent of groundwater level related to tectonic deformation,fault movement and active mantle uplift. Finally,we propose a“field-region-epicentre”evolution mode of dynamic pattern of sliding variation extent of groundwater level before and after the Tangshan earthquake.

Key words: Groundwater level anomaly, Tangshan earthquake, Dynamic pattern, Evolution mode

摘要： 对唐山地震前后地下水位动态图象的生成方法、时空演化特征及其形成演化模式的研究表明,唐山地震前后地下水位动态图象正负区和异常特征区的时空演化具有明显的规律性和阶段性。负值区的演化具有“收缩-扩展-急速扩展-发震”的特征;异常特征区的演化显示“迁移-扩展-稳定-发震-消失”的特征;滑动变差值显示“增大-减小-发震-急速减小”的变化过程。探讨了地下水位动态图象演化与构造变形、断层运动和上地幔物质上涌的关系,提出了唐山地震地下水位动态图象“场-区-源”的演化模式。

关键词: 地下水位异常, 唐山地震, 动态图象, 演化模式