对强震迁移的统计分析——以华北地区为例

The Statistical Analysis about Migration of Strong Earthquakes——Taking the North China Region as an Example

目前对强震迁移的研究多是集中在发现迁移现象方面 ,一些总结迁移规律的尝试则较为主观。本文认为 ,强震迁移如果具有规律性则其迁移指标应具有某种统计意义 ,并且对整体数据集的统计分析可避免传统迁移分析方法中的问题。通过对华北地区强震迁移的 3个指标 (迁移方位、迁移距离、迁移时间 )的统计分析 ,表明研究地区存在较明显的优势迁移方向 (西偏南 -东偏北方向 )、优势迁移距离 (10 0km内以及 30 0～ 70 0km范围 )和优势迁移时间间隔 (1年内以及 3～ 4年内 ) ,不同震级范围以及不同活跃期内的迁移特征略有区别。

The research on migration of strong earthquakes are mostly finding the phenomena. And some attempts on getting regularity are comparatively subjective. This paper holds the point that the index of migration should have statistical meaning if there is regularity about the migration of strong earthquakes. In this paper, three attributions on migration, i.e., migration direction,distance and time, are statistically analyzed. Results in the North China region show that the migration of strong earthquakes has statistical meaning. There have main migration direction (W by S-E by N),distance (≤100km and 300～700km), and time (≤1yr and 3～4yr). The migration features with different magnitude scope or phase have a bit variance.