摘要
综合运用噪声功率概率密度函数、双曲线正演建模及其联合似然性、插值网格时程等技术方法,从台网布局、地震监测与定位能力、预警能力与烈度速报精度等方面对青海地震预警站网的效能进行了系统性评估。获得的主要认识:(1)基于实际台基噪声水平计算了站网地震监测能力,结果显示:青海全省80%区域的地震监测能力可达到2.5级,重点预警区内局部可达1.2级;理论监测能力与基于PMC方法获得的概率最小完整性震级(M_(P))空间分布十分一致。(2)采用二维理论合成地震定位测试,清晰地揭示了预警站网中增加了基本站和一般站,使得定位精度有了明显提高,结果的系统性误差显著降低;按照水平误差及GT定义综合判断定位精度的准则评估的定位精度表明,全省重点预警区内的定位精度能达到Ⅰ类精度,其他区域范围内站点周围约30 km范围内能达Ⅱ类精度;震中位置偏差大于20 km区域主要位于青海西南部的监测能力薄弱区。(3)3个台触发条件下,在重点预警区内的预警首报时间约5.9 s,全省约20%的区域预警首报时间为10 s左右;重点预警区内的烈度速报精度可达10 km,90%置信度下全省80%的区域烈度速报精度约为70 km。
By comprehensively applying techniques such as the probability density function of noise power,hyperbolic forward modeling and its joint likelihood,and interpolation grid time series,this study systematically evaluated the performance of the Qinghai earthquake early warning station network.The evaluation focused on four aspects:station network layout,earthquake monitoring and location capability,early warning capability,and rapid intensity reporting accuracy.The main findings were as follows:(1)the seismic monitoring capabilities of the network were calculated based on the actual noise levels at the stations.The results showed that 80%of Qinghai Province could detect earthquakes with a magnitude of 2.5,while some areas within the key early warning zones could detect earthquakes with a magnitude as small as 1.2.These theoretical monitoring capabilities were highly consistent with the spatial distribution of the minimum completeness magnitude(MP)obtained using the PMC method.(2)Two-dimensional synthetic tests for theoretical earthquake locations revealed that the addition of basic and general stations significantly improved the location accuracy and greatly reduced systematic errors.The evaluation of the location accuracy based on the criteria combining horizontal error and GT definition indicated that the location accuracy in the key early warning zones of the province could reach Class Ⅰ,while Class Ⅱ accuracy could be achieved within approximately 30 km around the stations in other areas.Areas with epicenter deviations exceeding 20 km were mainly located in southwestern Qinghai where monitoring capabilities were weak.(3)Under the condition of threestation triggering,the initial early warning time in the key early warning zones was approximately 5.9 seconds,and in about 20%of the province,it was around 10 seconds.The rapid intensity reporting accuracy in the key early warning zones could reach 10 km,and at 90%confidence level,the accuracy in 80%of the province was approximately 70 km.
作者
万玉杰
马丽
吕弃暇
白占孝
王俊
赵燕杰
李玮杰
李振凯
张杰林
WAN Yujie;MA Li;LYU Qixia;BAI Zhanxiao;WANG Jun;ZHAO Yanjie;LI Weijie;LI Zhenkai;ZHANG Jielin(Qinghai Earthquake Agency,Xining 810000,China;Jiangsu Earthquake Agency,Nanjing 210014,China)
出处
《防灾减灾工程学报》
北大核心
2025年第4期961-968,共8页
Journal of Disaster Prevention and Mitigation Engineering
基金
地震科技星火项目(XH23015A)
中国地震局重大政策理论与实践问题研究课题“地震预警信息服务机制研究”
青海省地震科技基金项目(2025)资助。
关键词
理论合成地震定位
插值网格时程
最小完整性震级
定位精度
预警能力
烈度速报精度
theoretical synthetic seismic location
interpolation grid time series
minimum completeness magnitude
location accuracy
early warning capability
rapid intensity reporting accuracy
