THE VELOCITY MODEL IDENTIFICATION IN EARTHQUAKES PARAMETERS DETERMINATION IN THE NEAR REGIONAL OF THE BANGKA NPP CANDIDATE SITE

Abstract

Collecting information and earthquake investigation must be carried out to ensure the safety of the nuclear installation candidate site from seismic aspects. Accurate earthquake location data is essential for seismological studies. The accuracy must be improved from the velocity model factor in determining earthquake parameters in a limited number of stations and less azimuth coverage. The study aims to get the most appropriate velocity model for determining earthquake parameters in the near regional of the Bangka NPP candidate site. The study uses earthquake seismic data in Bangka seismic network with variations of the H-S, Crust 2.0, and TPI velocity models to determine earthquake parameters. The most appropriate velocity model is determined based on the comparison with BMKG results and the smallest errors in identifying earthquake parameters. The results show almost the same epicenter and origin time but different earthquake depths. The TPI velocity model best represents the velocity model in the near regional of the Bangka NPP candidate site. TPI falls into the criteria of tectonic earthquake type and most errors (latitude, longitude, and depth) in earthquake parameters determination are the smallest among other velocity models.