Abstract: Based on the measuing data from 9 observation points and the cases of 5 moderate earthquakes in North China during the time period from 1989 to 1991,the relationship between the anomaluos release of subsurface helium and hydrogen gasses and the occurrence time,locality and magnitude of earthquake has been discussed in this paper.An empirical method was proposed for determining the three main elements of earthquake prdeiction.It is proposed that the occurrence time of a possible earthquake can be predicted on basis of synchronus anomaly of helium and hydrogen in various observation points, and specially the dropping and truning of the curves of anomalies.The possible locality of earthquke occurrence can be delineated according to the fact that the starting time of the anomaly becomes later toward the epicentral area,i.e.the closer to the epicentral area,the later the starting time of the anomaly.The magnitude of the predicted earthquake can be estimated through the intensity (a combination of duration time and amplitade )and range of anomaly,as well as the number of the observation points that show anomalous release of helium and hydrogen gasses.

Key words: Gas geochemical surveys, Groundwater anomaly, Earthquake prediction, North China

摘要： 在系统整理华北9个气体观测井多年观测资料基础上,初步探讨了华北地下释放氦、氢异常的时、空、强特征及其与发震时间、地点、震级的关系,从而总结为以京棉二厂井的氦、氢异常为依据,其它测点的氦、氢异常为参考,预报华北北部5级以上地震的初步经验。

关键词: 氦氢异常, 时空强特征, 地震关系