云南地震预警站网监测效能评估  

Evaluation of the Monitoring Capability of the Yunnan Earthquake Early Warning Network

作　　者：朱杰 钟玉盛 ZHU Jie;ZHONG Yusheng(Yunnan Earthquake Agency,Kunming 650024,Yunnan,China)

机构地区：[1]云南省地震局,云南昆明650224

出　　处：《地震研究》2025年第3期422-431,共10页Journal of Seismological Research

基　　金：云南省地震局科技专项(2024ZX02).

摘　　要：选取2023年每个月中没有地震记录、人工干扰较小且记录完整的某一天的地震背景噪声数据,计算得出云南地震预警站网包含的3类地震仪器的噪声最大概率峰值位移(PGD)分布,并选择这3类地震仪器噪声最大的一个月(2月)对云南地震预警站网效能进行全面评估。利用考虑时效性的传统测震站网监测能力评估方法和混淆矩阵方法对云南地震预警站网3类地震仪器单独组网和融合组网的预警最小震级、预警首报时间和预警系统触发阈值进行研究。结果显示,测震仪、强震仪和烈度仪的PGD范围分别为0.004~0.048μm、0.04~2.85μm和7.5~26.9μm。云南地震预警站网监测能力下限由测震仪单独组网决定,平均值为M_(L)1.3,三网融合预警最小震级平均值为M_(L)2.7,云南55%的地区的预警最小震级小于M_(L)3.0,95%的地区小于M_(L)3.4。预警首报时间平均值为5.2 s,55%的地区小于5.1 s,95%的地区小于5.8 s。对于云南地震预警系统,提高其站点分布密度,一定程度上能够降低预警最小震级下限和减少预警首报时间。云南地震预警系统的触发阈值为M_(L)3.0,能满足实际站网监测工作需求,系统准确度为0.7797,精确度为0.8955,灵敏度为0.7595,特异性为0.8205,F1分数为0.8219。To study the warning effectiveness of the Yunnan Earthquake Early Warning Network,this paper selects the complete records of noise data of one day in each month of 2023,which has no earthquakes and less interference.The distribution of the peak ground displacement(PGD)of the three types of sensors is calculated,and the month(February)with the highest noise of the three types of sensors is chosen to conduct a comprehensive assessment of the warning network.By using the traditional monitoring capacity assessment method of seismic networks that considers timeliness and the confusion matrix method,this paper studies the minimum warning magnitude,the first report time after an earthquake,and the trigger threshold of the warning system for the three types of sensors when they are independently networked and in a combined network within the Yunnan Earthquake Early Warning Network.The results revealed that PGD of the seismometers'sensors ranged between 0.004-0.048μm,PGD of the accelerographs'sensors ranged between 0.04-2.85μm,and PGD of the intensity-meters'sensors ranged 7.5-26.9μm.The lower limit of the monitoring capability of the Yunnan Earthquake Early Warning Network is determined by the seismometer network it contains;its average is M_(L)1.3.The average value of the minimum magnitude for the Yunnan Earthquake Early Warning Network is M_(L)2.7,and in 55%of Yunnan area the early warning network can detect the magnitudes smaller than M_(L)3.0.In 95%of Yunnan area the early warning network can detect the magnitudes smaller than M_(L)3.4.The average time of the first-report for early warning after the earthquake is 5.2 s.For 55%of Yunnan area,the first-report time is less than 5.1 s.For 95%of Yunnan area,the reporting first-report time is less than 5.8 s.Increasing the station of the Yunnan Earthquake Early Warning System can help reduce the lower limit of the magnitude for early warning,and reduce the post-earthquake first report time.The triggering threshold of the Yunnan Earthquake Early Warning System is M_(L)3.

关 键 词：噪声水平 地震预警 监测能力 时效性 混淆矩阵 

分 类 号：P315.39[天文地球—地震学]