非测震学前兆异常的震情窗口效应

通过对１９７６年唐山７．８级、１９８３年菏泽５．９极和１９８９年大同６．１级．１９９１年大同５．８级四次地震的非测震学前兆异常（短水准、地电、水氡含量、水位等）的研究，发现在这些地震以前，邢台地区的非测震学前兆观测值均有异常出现，显示出该地区不仅有地震活动性的窗口效应，而且有非测震学前兆异常的震情窗口效应。其它地区也有相类似的情况存在。这对区域应力场研究和前兆场特征的研究具有重要意义，对强震的预报

WINDOW EFFECT OF SEISMIC SITUATION OF NON - SEISMOMETRIC PRECURSORY ANOMALY

Based on study of the non-seismometric precursory anomalies, such as the short - levelling, earth electricity, water Radon content and water level, during four earthquakes : Tangshan earthquake M = 7.8, 1976; Heze earthquake M=5.9, 1983; Datong earthquake M= 6.1, 1989 and Datong earthquake M- 5.8, 1991, it is found that the anomaly of observed values of those non-seismometric precursors occurred before these earthquakes in Xintai region, indicating that there is not only a window effect of seismic activity, but also the window effect of seismic situation in the region. The similar phenomenon is also found in other regions. The study on such an effect is significance of studying the regional stress field and the precursory field, and also helpful to prediction of strong earthquakes.