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本文阐述了开展近期强震危险性预测研究的科学依据及工作原则。从区域性地震群体活动的韵律性、分幕性及环境因子对地震发生的作用入手,研究了华北地震总形势。根据历史地震活动的时、空、强演变规律揭示了强震累计频度随时间的指数型分布特点。通过历次地震幕及各地震带之间的对比研究,判断了目前所处的地震活动阶段及各地震带的危险性程度。 然后探讨了确定地震危险区的准则和评选条件,考虑到强震区的地质结构、重磁异常和近期地震活动状况,利用图象识别方法,进行了地震活动区的识别和分类。 最后得到华北地区的地震总趋势为:目前仍处于1978年以来的地震平静幕时段,估计该平静幕持续10年左右,此时段内发生7级以上地震的可能性不大;此后地震活动将有所加强,可能有少量的6级乃至个别7级地震发生。已向有关方面提出了可能潜在的几个强震危险点。
This paper describes the scientific basis and working principle of carrying out the recent strong earthquake prediction. Beginning with the rhythmicity, subtopic nature of regional earthquake group activities and the effect of environmental factors on earthquakes, the general situation of the earthquake in North China is studied. According to the law of time, space, and strong evolution of historical seismicity, the exponential distribution of the cumulative frequency of strong earthquakes with time is revealed. Through the comparison between the seismic curtains and the seismic belts, the present stage of seismic activity and the dangerous degree of each seismic zone are judged. Then, the criteria and conditions for determining the seismic danger zone are discussed. Considering the geological structure, gravity and magnetic anomaly and the recent earthquake activity in the strong earthquake area, the image recognition method is used to identify and classify the seismic activity area. Finally, the general trend of the earthquakes in North China is as follows: It is still at the serene calm curtain since 1978, and it is estimated that the calm curtain lasts for about 10 years. It is unlikely that earthquakes of magnitude 7 or above will occur during this period. Earthquakes will have By strengthening, there may be a small amount of 6 or even 7 individual earthquakes. Several potential danger points for strong earthquakes have been put forward to relevant parties.