A study on analysis of earthquake parameter using LM (Levenberg-Marquardt) inversion algorithm

The ground environment in which we live is closely related to human life. Recently, as a large earthquake has occurred in the Korean peninsula, the importance of seismic stability evaluation of national important facilities and structures as well as auxiliary facilities such as life line is increasing. In this study, seismic source parameters and site-related attenuation parameters were analyzed by applying LM (Levenberg-Marquardt) inversion algorithm using three earthquake seismograms (from earthquakes near Baekyeong Island) observed at five stations (SND, HSB, TJN, MGB and SND) in the Korea peninsula. As a result of LM inversion using observed ground motions (3 earthquakes and 5 stations), the earthquake parameters such as seismic source and path operator show that the values for Q0, Δσ, and η are 353.1, 62.3 and 0.49, respectively. This is similar to the results of previous studies in Korea. High frequency seismic decay parameter (κ) for 5 stations was estimated. The arithmetic average of κ values of the 5 stations is 0.389, which is somewhat higher than previous domestic studies but it is similar to that of the western part of the US. It is necessary to study the seismic source and the attenuation parameter more accurately by using more large-scale seismic data in the future.