北京大学学报（自然科学版）2024，Vol.60Issue(4)：615-625,11.DOI:10.13209/j.0479-8023.2024.055
云南地区介质衰减、场地响应及震源参数研究
Study on Media Attenuation,Site Response and Source Parameters in Yunnan Area
摘要
Abstract
Based on the seismic waveform records of the Yunnan regional seismic network from 2012 to 2023,the joint inversion method was used to obtain the media attenuation Q value,the site response of 67 stations,and the source parameters of 2819 earthquakes above ML 2.0 in the study area.The results show that in Yunnan region,based on the geometric attenuation model of three seismic waves,the non elastic attenuation model accurately reflects the complex structure and strong seismic activity characteristics of the region.Among the 67 stations in the study area,the overall site response does not show much amplification effect,but there is obvious high-frequency attenuation phenomenon,and the amplification factor of the site in the excellent frequency band 1-6 Hz is mostly 1-4 times,while the attenuation of the site in the high band (above 10 Hz) is mostly between 0 to 95％.Among them,the site response value of 12 stations fluctuates around 1; the site response of the four stations is close to 1 at low frequency,and is amplified at high frequency.The overall response calculation result of the five stations is slightly less than 1.46 stations show a slight amplification at low frequency and attenuation at high frequency.Through the correlation analysis of the parameters of each seismic source,it is found that the local magnitude is positively correlated with moment magnitude,seismic moment,stress drop,apparent stress and radiant energy,and negatively correlated with corner frequency.In general,the aftershock areas of Yangbi,Yingjiang and Mangshi earthquakes in western Yunnan and the southern section of the Honghe fault in southern Yunnan have relatively high levels of stress relief from small and medium-sized earthquakes,while the areas along the Jinshajiang-Honghe fault zone,especially along the southern section of the Honghe fault zone in southern Yunnan,are concentrated areas of high stress and seismic drops,indicating that the faults here may be subjected to relatively strong tectonic shear stress.关键词
介质衰减/场地响应/震源谱/震源参数Key words
media attenuation/site response/source spectrum/source parameters引用本文复制引用
杨周胜,杨晶琼,张会苑,秦敏,许亚吉..云南地区介质衰减、场地响应及震源参数研究[J].北京大学学报（自然科学版）,2024,60(4):615-625,11.基金项目
国家重点研发计划(2021YFC3000703-01)资助 （2021YFC3000703-01）
