【摘要】 选取1970—2019年蒙宁交界区中国台网中心地震目录,结合研究区地质构造,分析震级与地震频次以及时间与地震频次的关系。利用极大似然法,设定不同的窗长和步长,对研究区进行b值时空扫描,对比b值时间曲线,发现某些中强震发生在b值下降到异常水平然后上升的过程。采用矩形窗和圆形窗分别进行空间扫描,对比发现,研究区低b值分布在(104°—105°E,36°—38°N)区域;对研究区16次中强震进行震例回溯,结果发现,5次地震发生在低b值区域,表明低b值区有发生中强震的可能。更多还原

【Abstract】 This paper uses the earthquake catalog of the Inner Mongolia-Ningxia junction area from 1970 to 2019 provided by the China Earthquake Networks Center,combined with the geological structure of the study area,to analyze the relationships between magnitude and earthquake frequency and between time and earthquake frequency.This paper uses the maximum likelihood method to scan the b-value in the study area in time and space domains and compares b-value curves for different window lengths and step lengths.It was found that some moderate earthquakes occurred during the process when the b value dropped to an abnormal level and then rose again.Spatial scanning was carried out using rectangle and circular windows for comparison.It is found that the low b-value in the study area is in the area of 104°—105°E and 36°—38°N.We carried out retrospective research for 16 moderate earthquakes in the study area,the results show that 5 earthquakes occurred in low b-value areas,indicating that moderate earthquakes may occur in low b-value areas.更多还原