寻乌及邻区遗漏地震检测及目录完整性分析

Missing Earthquakes Detection and Integrity Analysis of Earthquake Catalogue in Xunwu and Its Adjacent Area

利用匹配滤波技术对寻乌及邻区2009年1月—2020年12月的遗漏地震事件进行检测,共检测到遗漏地震306个,约为台网目录的40%,ML1.5以下地震的目录完整性有较明显的改善。增加遗漏地震后b值从0.885变为0.917。区域内的寻乌、平远和安远震群分别检测到遗漏地震36个、15个、8个,约为原震群目录的1/2、1/3和1/5,遗漏地震比例与模板地震数量关系密切。补充遗漏地震后寻乌震群ρ值判定结果由非前兆变为前兆,表明遗漏地震检测对前兆震群识别有重要影响。

Using the matched filtering technology to detect the missing earthquake events in Xunwu and its adjacent area from January 2009 to December 2020,a total of 306 missing earthquakes were detected,which is about 40%of the network catalog,and the catalog integrity of earthquakes below ML1.5 has been significantly improved.The b value changes from 0.885 to 0.917 after adding missed earthquakes.The 36,15 and 8 missing earthquakes were detected in Xunwu,Pingyuan and Anyuan earthquake swarms in the region,which are about 1/2,1/3 and 1/5 of the original earthquake swarm catalogue,and the proportion of missing earthquakes is closely related to the number of template earthquakes.The determination result of theρvalue of the Xunwu earthquake swarm changes from non-precursor to precursor after the supplementing the missing earthquakes,indicating that the missing earthquakes detection has an important influence on the identification of precursory earthquake swarm.