基于b值的晋冀鲁豫交界区强震背景研究

以晋冀鲁豫交界区为研究对象, 利用古登堡的频次与震级关系式, 计算1970年1月~2018年6月该区b值, 进而判断未来强震危险地段。 计算结果显示, 邢台震源区西南端的未破裂区域为低b值异常区。 进一步研究该区的地壳物性结构等资料, 认为其具有高低速相间的地壳介质、 深切地幔的断裂、 大地震破裂空段等利于能量积累、 发生强震的特性。 综合分析认为, 低b值异常区附近的紫山西断裂与曲陌断裂交会区, 是未来晋冀鲁豫交界区最有可能发生强震的区域。

Study on Strong Earthquake Background in the Junction Area of Shanxi,Hebei, Shandong and Henan Based on b Value

Taking the junction area of Shanxi, Hebei, Shandong and Henan as the research object, the b value of the area from January 1970 to June 2018 is calculated by using the relationship between frequency and magnitude of Gutenberg, and then the dangerous area of strong earthquakes is judged in the future. The results show that the area of Xingtai at the southwestern end of the Xingtai earthquake source area is a low b value anomal area. By studying the crustal physical properties and structure in this area, it is considered that it has the characteristics of high and low velocity crustal medium, deep mantle faults and large earthquake rupture gap and other characteristics, which are conducive to energy accumulation and strong earthquakes. Comprehensive analysis shows that region on southwest of the Xingtai earthquake source area are the areas where strong earthquakes are most likely to occur in the junction area of Shanxi, Hebei, Shandong and Henan in the future.