大同和张北地震震前地震活动异常对比研究

Comparative study on abnormal seismicities before Zhangbei Earthquake and Datong earthquake

对1989年大同6.1级地震和1998年张北6.2级地震前,华北地区以及震中附近出现的长、中、短期地震活动异常进行了研究,结果表明,二次地震前有较多相似的地震活动异常出现,并且异常的空间位置也相似。分析认为,产生这些相似异常现象的原因是由于二次地震的孕育都与山西断陷带和张家口 渤海断裂带活动有关。震前短期阶段多次出现小震活动沿断裂带有序分布,表明强震前孕震构造控震能力增强。

In this paper, we studied the long, mid- and short-term abnormal seismicities before Zhangbei and Datong earthquakes in North China. We found that there were a lot of similar abnormal seismicities and attempted to explain them. We suggest that the reason of the similar abnormal seismicities was the Datong earthquake and Zhangbei earthquake, related to Shanxi tectonic zone and Zhangjiakou-Bohai tectonic zone. Similar tectonic environment resulted in these similar abnormal phenomena.