NLLoc定位方法在福建地区的适用性探究  

Preliminary Study on the Applicability of NLLoc Method in Fujian Area

作　　者：张丽娜[1] 张红才[1] 巫立华[1] 段刚[1] 戴丽金[1] 廖诗荣[1] ZHANG Lina;ZHANG Hongcai;WU Lihua;DUAN Gang;DAI Lijin;LIAO Shirong(Fujian Earthquake Agency,Fuzhou 350003,China)

机构地区：[1]福建省地震局,福州350003

出　　处：《华南地震》2021年第1期34-43,共10页South China Journal of Seismology

基　　金：福建省地震局局科技基金项目(SF202011)。

摘　　要：利用非线性定位方法NLLoc,对22次人工定点爆破事件和88次福建仙游震群序列M≥1.5级地震事件进行重新定位,并与福建台网日常定位方法进行对比,讨论了NLLoc方法在台网日常业务应用中的可行性。研究结果表明,NLLoc算法无论是人工爆破还是天然地震,其定位结果在发震时刻误差、震中误差和震源深度误差等方面都优于现有定位方法结果,尤其是在震源深度确定方面NLLoc算法优势明显。该方法定位仙游序列活动初期深度较浅与CAP反演2012年4月15日M_(L) 4.1级地震的震源深度一致,地震序列活动中后期深度均值略小于理论估值;而正式目录的地震序列活动初期深度较深,震源深度差值较大,地震序列活动中期深度均值大于理论估值。NLLoc方法可用于台网日常地震定位,且有助于更好地解决震源深度测定问题,提高地震定位精度。By using the nonlinear location method NLLoc,the paper relocated 22 explosion events and the 88 events of Xianyou earthquake swarm sequence with M≥1.5 in Fujian,compared with the daily location methods of Fujian network,and discussed the feasibility of the NLLoc method in the daily application of the network.The results show that the NLLoc method is superior to the common location methods in terms of origin time error,epicenter error and depth error,and especially the NLLoc algorithm has obvious advantages in determining the focal depth.The initial depth of Xianyou sequence activity is shallow,which is consistent with the depth of the event M_(L) 4.1 retrieved by CAP occurred On April 15th,2012,and the average depth of the seismic sequence activity in the middle and late periods is slightly smaller than the theoretical estimation.While the seismic sequence activity in the official catalogue has a deeper initial depth and a large difference in focal depth,and the average mid-term depth of seismic sequence activity is greater than the theoretical estimation.In summary,the NLLoc method can be used for daily earthquake location of the network,which is better to solve the problem of focal depth measurement and expected to improve seismic location accuracy.

关 键 词：NLLoc方法 地震定位 发震时刻误差 震中误差 深度误差 

分 类 号：P315.7[天文地球—地震学]