蒙古国及其周边地区地震分形维度及b值研究

Fractal Dimension and b-value of Earthquakes in Mongolia and Its Surrounding Area

摘要:

根据蒙古国及其周边地区的地震目录，计算了蒙古国地区地震的空间分形维度D值和震级—频度关系中的b值。结果表明蒙古国地区地震空间分形维度D值约为1.56，说明了蒙古国地区地震空间分布具有一定的丛集性。蒙古国地区b值约为0.962，非常接近1，说明蒙古国地区是一个典型的地震活动区。我们还分析了b值和D值随深度变化情况，结果揭示了蒙古国地区地壳介质结构的各向异性程度和应力分布的空间差异。文中研究结果还表明蒙古国地区地震的b值和D值呈现正相关性。

Abstract:

Fractal （correlation）dimension and b-value are determined from seismic catalog recorded in Mongolia and its surrounding area.The spatial correlation of 1.56 is indicative of more or less clustered events in the region, while a b-value of 0.962 implies a highly active seismic region.A detailed study of the frequency-magnitude distribution and fractal dimension as a function of depth is also made.The results suggest structural variability at different depth levels in the Mongolia seismic zone that reflects highly heterogeneous and differential stress distribution in the region. Our result also shows that positive is the relationship between the b-value of the Gutenberg-Richter relation and the fractal dimension D of earthquakes in Mongolia region.