The 348 microearthquakes that occurred in Beijing and its neighboring areas(39°-41°,114°-117°E)during 1979 to March of 1992 are relocated in this study.Precision of hypocenter locations is improved...The 348 microearthquakes that occurred in Beijing and its neighboring areas(39°-41°,114°-117°E)during 1979 to March of 1992 are relocated in this study.Precision of hypocenter locations is improved by rechecking and supplementing readings of arriving times of the seismic phases used,testing and selecting the appropriate crustal model,and modifying the computer program.After the relocation,the number of earthquakes with focal depth determination has been increased to 313 from the previous 132.The overall average RMS residual of the observational arrival times has been reduced to 0.45±0.18 s from the previous value of 0.80±0.40 s.Nearly 10% of the relocated hypocenters,which are mostly in border regions of the area covered by the Beijing Telemetered Seismic Network,have been shifted more than 10 km.Epicenters of the relocated earthquakes are concentrated in the intermountainous basins,such as the Huai’an,Xuanhua,Huailai,and Zhuolu basins,and are related with the basin boundary faults between展开更多
A query regarding the now commonly accepted epicentral location of the 1216 Mahu earthquake in Leibo County, Sichuan Province is proposed after examination of local historical records of earthquakes, field investigati...A query regarding the now commonly accepted epicentral location of the 1216 Mahu earthquake in Leibo County, Sichuan Province is proposed after examination of local historical records of earthquakes, field investigation of the Mahu barrier lake, study of geological environment for the earthquake and the available data then a relocation of the earthquake epicenter is suggested in the paper.展开更多
基金This project was sponsored by the State Science and TechnologyCommission and State Seismological Bureau (85-907-04-01),China.Contribution No.95A0051.Instirute ofGeophysics,SSB,China.
文摘The 348 microearthquakes that occurred in Beijing and its neighboring areas(39°-41°,114°-117°E)during 1979 to March of 1992 are relocated in this study.Precision of hypocenter locations is improved by rechecking and supplementing readings of arriving times of the seismic phases used,testing and selecting the appropriate crustal model,and modifying the computer program.After the relocation,the number of earthquakes with focal depth determination has been increased to 313 from the previous 132.The overall average RMS residual of the observational arrival times has been reduced to 0.45±0.18 s from the previous value of 0.80±0.40 s.Nearly 10% of the relocated hypocenters,which are mostly in border regions of the area covered by the Beijing Telemetered Seismic Network,have been shifted more than 10 km.Epicenters of the relocated earthquakes are concentrated in the intermountainous basins,such as the Huai’an,Xuanhua,Huailai,and Zhuolu basins,and are related with the basin boundary faults between
文摘A query regarding the now commonly accepted epicentral location of the 1216 Mahu earthquake in Leibo County, Sichuan Province is proposed after examination of local historical records of earthquakes, field investigation of the Mahu barrier lake, study of geological environment for the earthquake and the available data then a relocation of the earthquake epicenter is suggested in the paper.
