中国大陆地震活动高潮期与平静期水化学变化特征及其意义的研究

STUDY ON THE CHARACTERISTICS OF HYDROCHEMICAL CHANGE DURING THE HIGH AND LOW SEISMICITY PERIODS ON CHINA CONTINENT

本文根据对华北、南北地震带等大范围内２０多个（总共约４０个）主要水化学（水氡）观测点近２０年连续变化曲线的分析，发现１９６６─１９７６年地震活动高潮期均呈现趋势性高值异常，突变异常比较普遍。１９７７─１９８５年地震活动相对平静期则呈现平稳的正常值变化，只是在局部地区的个别测点出现短趋势异常或突变异常。由此认为地震活动高潮期大区域应力场作用下形成大范围水化学异常场，这是预报连发性大震的一个重要标志。

In terms of analysis on the continuous change curves of radon in groundwater at morethan twenty measuring points along the north China and North-South tectonic belt,it is foundthat the tendenciously high value anomaly and abrupt anomaly were common during the highseismicity period from l966 to l976.But during the low seismicity period from 1977 to 1985,the groundwater radon value is stable except the short-term tendency anomly or abrupt anoma-ly at few points in local area,It is considered that the hvdrochemical anomaly field under theaction of the regional stress field during high seismicity period is an importaI1t indication for theprediction of one-by-one strong events.