Machine learning-based automatic construction of earthquake catalog for reservoir areas in multiple river basins of Guizhou province,China  

作　　者：Longfei Duan Cuiping Zhao Xingzhong Du Lianqing Zhou 

机构地区：[1]Institute of Earthquake Forecasting,China Earthquake Administration,Beijing 100036,China [2]PowerChina Guiyang Engineering Corporation Limited,Guiyang 550081,China

出　　处：《Earthquake Science》2023年第2期132-146,共15页地震学报（英文版）

基　　金：the Science and Technology Project of Power Construction Corporation of China Ltd.(No.DJ-ZDXM-2020-55).

摘　　要：Large reservoirs have the risk of reservoir induced seismicity.Accurately detecting and locating microseismic events are crucial when studying reservoir earthquakes.Automatic earthquake monitoring in reservoir areas is one of the effective measures for earthquake disaster prevention and mitigation.In this study,we first applied the automatic location workflow(named LOCFLOW)to process 14-day continuous waveform data from several reservoir areas in different river basins of Guizhou province.Compared with the manual seismic catalog,the recall rate of seismic event detection using the workflow was 83.9%.Of the detected earthquakes,88.9%had an onset time difference below 1 s,81.8%has a deviation in epicenter location within 5 km,and 77.8%had a focal depth difference of less than 5 km,indicating that the workflow has good generalization capacity in reservoir areas.We further applied the workflow to retrospectively process continuous waveform data recorded from 2020 to the first half of 2021 in reservoir areas in multiple river basins of western Guizhou province and identified five times the number of seismic events obtained through manual processing.Compared with manual processing of seismic catalog,the completeness magnitude had decreased from 1.3 to 0.8,and a b-value of 1.25 was calculated for seismicity in western Guizhou province,consistent with the b-values obtained for the reservoir area in previous studies.Our results show that seismicity levels were relatively low around large reservoirs that were impounded over 15 years ago,and there is no significant correlation between the seismicity in these areas and reservoir impoundment.Seismicity patterns were notably different around two large reservoirs that were only impounded about 12 years ago,which may be explained by differences in reservoir storage capacity,the geologic and tectonic settings,hydrogeological characteristics,and active fault the reservoir areas.Prominent seismicity persisted around two large reservoirs that have been impounded for less than 10 yea

关 键 词：river basins in Guizhou reservoir earthquake machine learning earthquake location B-VALUE 

分 类 号：P315.7[天文地球—地震学]