摘要
极值统计是研究较少发生但一旦发生即产生极大影响的随机事件的有效方法。本文以地震活动频繁的昆仑山地区作为研究区域,建立了基于广义帕累托分布的超阈值(POT)模型,并讨论了该地区若干地震活动性参数,包括强震震级分布、潜在震级上限、强震平均复发间隔、一定周期内的强震发震概率、一定时期内的重现水平和超定值重现震级。经统计分析得到:该地区震级阈值选定为 M_(s)5.5,超阈值期望震级为 M6.81,潜在震级上限高达 M9.08,M8.0 的平均复发间隔仅为 66.8 年,未来 3 年该地区发生 M_(s)5.5~M_(s)6.5 的概率在 80% 以上,百年重现水平即可达到历史最大震级MS8.1。
Extreme value statistics is an effective method to study random events that rarely occur but can cause great impact once they occur. This article takes the Kunlun Mountains area with frequent seismic activities as the research area. We establish a peaks over threshold (POT) model based on the generalized Pareto distribution. Then we discuss several seismic activity parameters, including:strong earthquakes magnitude distribution, upper limit of potential magnitude, average recurrence period, probability of strong earthquakes in a certain period in the future, the recurrence level and expected recurrence magnitude in a certain period. According to statistical analysis, the magnitude threshold of the region is selected as MS5.5. The expected magnitude over the threshold is MS6.81 and the upper limit of potential magnitude is MS9.08. The average recurrence period of MS8.0 is only 66.8 years. The probabilities of MS5.5 ~MS6.5 are all above 80%. The 100-year return period can reach the historical maximum magnitude MS8.1.
作者
任晴晴
赵宜宾
钱小仕
李科长
张艳芳
Ren Qingqing;Zhao Yibin;Qian Xiaoshi;Li Kechang;Zhang Yanfang(Institute of Disaster Prevention,Sanhe 065201,Hebei,China;State Key Laboratary of Earthquake Dynamics,Institute of Geology,China Earthquake Administration,Beijing 100029,China)
出处
《震灾防御技术》
CSCD
北大核心
2022年第3期529-538,共10页
Technology for Earthquake Disaster Prevention
基金
中央高校基本科研业务费项目(ZY20140203,ZY20210311)
河北省地震科技星火计划项目重点项目(DZ20200827053)
河北省高等学校科学技术研究项目(Z2020224)。
关键词
广义帕累托分布
超阈值(POT)模型
潜在震级上限
重现水平
Generalized pareto distribution
Peaks over threshold model
Potential maximum magnitude
Recurrence level
