郯庐断裂带苏皖段及邻区b值时空特征研究  

Research on the b -Value Space-Time Characteristics in Jiangsu-AnhuiSection and Adjacent Area of Tan-Lu Fault Zone

作　　者：余腾[1] 王鑫[2] 李明峰 朱益民 孙小荣[1] YU Teng;WANG Xin;LI Mingfeng;ZHU Yimin;SUN Xiaorong(School of Civil Engineering and Architecture,Suqian College,399 South-Huanghe Road,Suqian 223800,China;Institute of Crustal Dynamics,CEA,1 Anningzhuang Road,Beijing 100085,China;School of Geomatics Science and Technology,Nanjing Technology University,30 South-Puzhu Road,Nanjing 211800,China)

机构地区：[1]宿迁学院建筑工程学院,江苏省宿迁市223800 [2]中国地震局地壳应力研究所,北京市安宁100085 [3]南京工业大学测绘科学与技术学院,南京市211800

出　　处：《大地测量与地球动力学》2021年第2期173-179,共7页Journal of Geodesy and Geodynamics

基　　金：国家自然科学基金(41274009,41574022);宿迁市科技计划(K201914);江苏省高校自然科学研究面上项目(20KJB170009)

摘　　要：采用郯庐断裂带苏皖段及邻区近50 a的地震数据,在定量分析区域最小完备震级M C和推导b值计算的极大似然法基础上,重点研究G-R关系,尤其是b值时空分布演化特征,并依据b值指示意义进行5级以上地震关联性和断裂带影响区域的构造应力分布状况分析。结果显示,依据b值的时间分布特征,研究区中强地震发生时段与中短期b值下降时段关联率达到80%以上;依据b值的空间分布特征,研究区苏北盆地整体及以南和合肥盆地南缘范围内的地壳应力较高,与超高压变质带的分布有较好的一致性,结合相关地质资料认为,该区域处于孕震阶段。We take the data of local earthquakes in Jiangsu-Anhui section and adjacent area of Tan-Lu fault zone in recent 50 years as data samples.Based on the quantitative analysis of the minimum complete magnitude(M C)of this area,and the systematically derived principle of the maximum likelihood method for the calculation of b-value,this paper focuses on the study of the G-R relationship in the area,especially the evolution characteristics of the temporal and spatial distribution of the b-value.According to the indication of the b-value,the correlation between the b-value and earthquakes with M L≥5 in the area,and the distribution of the crustal tectonic stress indicated by the b-value,are analyzed.According to the characteristics of the temporal distribution of b-value,the period of occurrence of moderate and strong earthquakes obviously coincides with the period of medium and short-term decline of b-value,and the correlation rate is over 80%.The spatial distribution of b-value indicates that the crustal stress of the whole north Jiangsu basin,the south of the basin and the southern margin of Hefei basin,is relatively high;it is consistent with the distribution of UHP metamorphic belt in the region.Combined with relevant geological data,we infer that the region is in the stage of earthquake preparation.

关 键 词：郯庐断裂带 苏皖段 G-R关系 B值 时空分布 

分 类 号：P315[天文地球—地震学]