基于概率的震级完备度方法评估云南地震台网的监测能力

(云南省地震局,云南 昆明 650224)

完备震级; 地震监测能力; PMC方法; 云南地震台网; 检测概率; 空间分布

Assessment of Detectability of the Yunnan Seismic Network by Using the Probability-based Magnitude of Completeness Method
YANG Zhousheng,YANG Jingqiong,LIU Pengfei,LYU Shuai,YAO Yuan

(Yunnan Earthquake Agency,Kunming 650224,Yunnan,China)

complete magnitude; earthquake monitoring capability; the PMC method; the Yunnan Seismic Network; detectability probability; spatial distribution

DOI: 10.20015/j.cnki.ISSN1000-0666.2025.0007

备注

为了科学评估云南地震台网的监测能力,分析云南地区的地震监测能力时空分布特征,采用基于概率的震级完备度(PMC)方法,利用2009—2023年云南地震台网地震目录、震相和台站信息等数据,计算了云南地震台网在云南地区的平均地震监测能力和在不同深度的监测能力,得到滇中、滇西局部地区的基于概率的完备性震级MP=1.5,云南全境基本都能监测到2.5级地震。评估了研究时段内云南地震台网台站监测能力的演变,发现部分台站的监测能力持续下降。但自2018年增加20个台站后,云南2.0及2.5级地震的监测范围有一定的扩大,但微震监测能力提升不明显,可能是因为2018年以来云南一直处于小震弱活动状态。最后,对应用PMC方法规划提升台网监测能力进行了展望。
In order to assess the monitoring capacity of the Yunnan Seismic Network,and analyze the characteristics of the spatial and temporal distribution of the Network's monitoring capacity in Yunnan,we select the earthquake catalogs,seismic phases,and station information during the period of 2009-2023,and use the probability-based magnitude of completeness(PMC)method to compute the average monitoring capacity of the Network,and the capacity at different depths.We obtain that MP value in some parts of central and western Yunnan reaches 1.5,and throughout Yunnan,the Network is capable of monitoring 2.5-magnitude earthquakes.The evolution of the Network's monitoring capacity over the past 15 years is assessed,and some stations' monitoring capacity has been declining,and after 20 new stations having been built in 2018,the monitoring range of 2.0-magnitude and 2.5-magnitude earthquakes of the Network in Yunnan has been expanded,but the Network's capacity of monitoring micro-earthquakes is not improved significantly.Perhaps the reason is that small earthquakes in Yunnan is very inactive since 2018.Finally,an outlook for the application of the PMC method for improving the monitoring capacity of the seismic network is put forward.