【摘要】 讨论了唐山地震前后水氡变化率动态图象的时空演化特征．用水氡月均值的变化率做参量，绘制每月的变化率平面等值线图，得到水氡的变化率动态图象．研究表明，唐山地震前震中周围出现水氡变化率≥０．０６的异常特征区．异常特征区的面积具有“扩展—收缩”的特点，并显示出阶段性．更多还原

【Abstract】 Characteristics of time space evolution of dynamic pattern of radon content in groundwater are discussed. Isograms of monthly variation rate of radon content in groundwater are drawn, which is dynamic pattern of the variation rate. The result shows that anomaly characteristic region appeared around the epicenter in which variation rate of radon content is over 0.06 before the Tangshan earthquake.Area of the characteristic region expanded first and then narrowed with time, showing two stages.更多还原