摘要
依据“固定质量法”的定义及原理,本文给出了一种判断地震空间分布分形结构及计算D_q的方法。利用该方法对华北地区地震的空间分布特征进行了初步研究。结果表明,在满足一定的统计条件下,不同区域范围内、不同时间段的地震分布均具有分形结构。围绕海城、唐山大震区分别选择4个大小不同的区域,分不同时段计算其D_q—q谱。结果表明,强震前后其形态无显著变化。强震前在较大的区域范围内,D_o值有降低的趋势,震后回升;在震源区周围较小区域内,D_o的变化相反;而有的区域强震前后D_o值没有变化。
According to. the definition and ,,principle of' fixed mass method' , a numerical method is given in this paper, which can be used to judge, the earthquake Space-distribution fractal and calculate its dimension. Using this method, the features of earthquake, distribution in North China is studied. The results. Show that satisfying certain statistic conditions, the earthquake distribution belongs fractal in different areas and periods. Selecting different areas and periods in the epicentral areas of the Tangshah and Haicheng earthquakes, the D_q—q spectra are calculated. The ,results show that there is no marked change for the D_q versus q curves before and after the strong earthquakes. The results also show that for large areas, the Do value has reducing trend before strpng earthquakes, and increase after the events; it is opposite for small areas; and for some areas, the D_0seldom changes before and after strong events.
出处
《西北地震学报》
CSCD
1993年第1期61-66,共6页
Northwestern Seismological Journal