采用基于概率的最小完整性震级方法（PMC），对青海省测震台网稳定运行以来实际产出的地震观测报告数据（2014—2021年）进行分析，获得该台网单台检测概率（PD）、合成检测概率（PE）以及基于概率的最小完整性震级（MP）的空间分布。通过对青海及邻区地震监测能力的评估，获得如下认识：青海测震台网监测能力存在明显的空间差异，其中：在台站分布较为密集的青海东部、中部地区，地震监测能力较好，MP分别为ML 1.5—2.0和ML 1.8—2.5；在台站分布较为稀疏的青海西部和南部地区，地震监测能力则相对较差，MP分别为ML 2.5—3.5和ML 2.2—2.7；在台站分布最为稀疏的青藏交界地区，地震监测能力最差，MP约为ML 2.5—3.5。对青海测震台网监测能力的科学评估，可为进一步改善台网空间布局提供参考依据。
This study analyzes seismic observations of the Qinghai Regional Seismic Network after its stable operation (20140101-20211231) based on the probability-based magnitude of completeness (PMC) method to obtain the spatial distributions of single station detection probability (PD), synthetic detection probability (PE), and the probability-based magnitude of completeness (MP). Through the evaluation of the seismic monitoring capability in Qinghai and its adjacent areas, the following conclusions are obtained:the monitoring capability of the Qinghai Seismic Network has obvious spatial differences. In eastern and central areas of Qinghai where the stations are more densely distributed, the seismic monitoring capability is better, with MP values of ML 1.5-2.0 and ML 1.8-2.5, respectively. In the western and southern areas of Qinghai where the stations are sparse, the seismic monitoring capability is relatively poor, with MP values of ML 2.5-3.5 and ML 2.2-2.7, respectively. The seismic monitoring capability is the worst in the Qinghai-Tibet border area where the stations are most sparsely distributed, with an MP value of about ML 2.5-3.5. The scientific evaluation of the monitoring capability of Qinghai Seismic Network can provide a reference for further improving the spatial layout of the network.
2022,43（5）: 23-32 收稿日期：2022-05-09
DOI：10.3969/j.issn.1003-3246.2022.05.004
基金项目：2022年青海省地震局地震科学基金课题（项目编号：2022B01）；2022年度震情跟踪定向工作任务（项目编号：2022010504）；青海格尔木青藏高原内部地球动力学野外科学观测研究站专项
作者简介：郭瑛霞(1990-),女,助理工程师,毕业于中国地震局兰州地震研究所,硕士学位,主要从事地震活动性和数字地震学方面的研究工作。E-mail:932319938@qq.com
*通讯作者：顾勤平,男,博士,高级工程师,主要从事天然地震层析成像、浅层人工地震勘探及活动断层探测工作。E-mail:gqp1221@163.com
参考文献：
安祥宇,赵倩,王晓睿,等.基于PMC方法的辽宁测震台网监测能力评估[J].地震工程学报,2019,41(6):1 545-1 552.
冯建刚,蒋长胜,韩立波,等. 甘肃测震台网监测能力及地震目录完整性分析[J]. 地震学报,2012,34(5):646-658.
韩立波,蒋长胜,李艳娥,等. 用于地震可预测性CSEP计划的南北地震带地区地震最小完整性震级Mc研究[J]. 地震,2012,32(1):17-27.
蒋长胜,房立华,韩立波,等. 利用PMC方法评估地震台阵的地震检测能力——以西昌流动地震台阵为例[J]. 地球物理学报,2015,58(3):832-843.
刘芳,蒋长胜,张帆,等. 内蒙古区域地震台网监测能力研究[J]. 地震学报,2014,36(5):919-929.
李智超,黄清华.基于概率完备震级评估首都圈地震台网检测能力[J].地球物理学报,2014,57(8):2 584-2 593.
青海省地方史志编纂委员会. 青海省志-地震志[M]. 西宁:青海人民出版社,2018:100-146.
司政亚,钟世军,林向东,等. 基于PMC方法分析北京及邻区地震监测能力[J]. 地震地磁观测与研究,2021,42(Z1):70-72.
王鹏,郑建常,李铂. 基于PMC方法的山东省测震台网监测能力评估[J]. 地球物理学进展,2016,31(6):2 408-2 414.
王鹏,毕波,林航毅,等. 基于PMC方法的上海测震台网地震监测能力评估[J]. 地震地磁观测与研究,2020,41(5):18-24.
王亚文,蒋长胜,刘芳,等. 中国地震台网监测能力评估和台站检测能力评分(2008-2015年)[J].地球物理学报,2017,60(7):2 767-2 778.
余娜,张晓清,杨晓霞. 青海及邻区地震目录最小完整性震级分析[J]. 地震,2020,40(4):23-32.
中国地震局监测预报司.数字地震观测技术[M].北京:地震出版社,2003:521-522.
Enescu B, Ito K. Spatial analysis of the frequency-magnitude distribution and decay rate of aftershock activity of the 2000 Western Tottori earthquake[J]. Earth, Planets and Space, 2002, 54(8):847-859.
Gentili S,Sugan M,Peruzza L,et al.Probabilistic completeness assessment of the past 30 years of seismic monitoring in northeasternItaly[J].Phys Earth Plane Inter, 2011, 186(1/2):81-96.
Gomberg J, Reasenberg P A, Bodin P, et al. Earthquake triggering by seismic waves following the Landers and Hector Mine Earthquakes[J]. Nature, 2001, 411(6 836):462-466.
Knopoff L. The magnitude distribution of declustered earthquakes in Southern California[J]. Proc Nat Acad Sci USA, 2000, 97(22):11 880-11 884.
Main I. Apparent Breaks in Scaling in the Earthquake Cumulative Frequency-Magnitude Distribution:Fact or Artifact[J]. Bull Seismol Soc Am, 2000, 90(1):86-97.
Mignan A, Werner M J, Wiemer S, et al. Bayesian estimation of the spatially varying completeness magnitude of earthquake catalogs[J]. Bull Seismol Soc Am, 2011, 101(3):1 371-1 385.
Mignan A, Jiang C, Zechar J D, et al. Completeness of the Mainland China earthquake catalog and implications for the setup of the China earthquake forecast testing center[J]. Bull Seismol Soc Am, 2013, 103(2A):845-859.
Nanjo K Z, Schorlemmer D, Woessner J, et al. Earthquake detection capability of the Swiss Seismic Network[J]. Geophysical Journal International, 2010, 181(3):1 713-1 724.
Ogata Y, Katsura K. Analysis of temporal and spatial heterogeneity of magnitude frequency distribution inferred from earthquake catalogues[J]. Geophysical Journal International, 1993, 113(3):727-738.
Stein R S. The role of stress transfer in earthquake occurrence[J]. Nature, 1999, 402(6 762):605-609.
Schorlemmer D, Woessner J. Probability of Detecting an Earthquake[J]. Bull Seismol Soc Am, 2008, 98(5):2 103-2 117.
Wiemer S, Wyss M. Minimum Magnitude of Completeness in Earthquake Catalogs:Examples from Alaska, the Western United States, and Japan[J]. Bull Seismol Soc Am, 2000, 90(4):859-869.
Woessner J, Hauksson E, Wiemer S, et al. The 1997 Kagoshima (Japan) earthquake doublet:A quantitative analysis of aftershock rate changes[J]. Geophysical Research Letters, 2004, 31(3):L03605.
