论文部分内容阅读
归纳了自1975年以后华北地区13次中强以上地震的地壳形变短临前兆异常60例。统计地壳形变短临异常与地震的定性关系，发现距震中较远的台站异常出现较早，较近的台站异常出现较晚，地震的震级与异常的空间展布范围成正比，异常往往倾向震中或背向震中。跨断层的位移型形变异常形态有两大类：一类是趋势性异常变化，另一类是高频波动。本文提出了将连续型形变转化为应变的方法。从1989年10月16日大同－阳高61级地 震和1991年3月26日大同－阳高5．8缓地震的实例可见，地震往往发生在高应变区或其附 近，异常量级可达10－6。
Sixty cases of short-term precursory anomalies of crustal deformation were summarized since the mid-strong earthquakes of more than 13 strong earthquakes in North China since 1975. The qualitative relationship between short anomalies of crustal deformation and earthquakes was statistically analyzed. It was found that stations anomalies occurred far away from the epicenter, late anomalies appeared nearer, and magnitude of the earthquakes was proportional to the spatial distribution of anomalies, Tendency epicenter or back epicenter. There are two main types of displacement-type deformation anomalies across the fault: one is the trend of abnormal changes, and the other is high-frequency fluctuations. This paper presents a method of converting continuous deformation into strain. From the example of the Datong-Yanggao MS6.1 earthquake on October 16, 1989 and the Datong-Yanggao 5.8 mild earthquake on March 26, 1991, we can see that the earthquake often occurs at or near the high-strain region with anomalous magnitude 10-6.