The 2020 National Seismic Hazard Model for Georgia (Sakartvelo)

Abstract

AbstractThe Earthquake Model of the Middle East (EMME) project paved the road to a state-of-the-art seismic hazard assessment in the region, including Georgia as one of the key participants. After the EMME project, the Institute of Geophysics initiated the revision of the national seismic hazard model of Georgia, in light of the new findings of the EMME project, new harmonized datasets, fully aligned with the probabilistic framework promoted by the Global Earthquake Model (GEM). In this contribution, we present the main elements of a newly developed seismic hazard model for Georgia. We started with the updating of the regionally harmonized datasets (i.e. earthquake catalogues, area seismic sources) with focus on data collected in the recent years. The seismogenic source model consists of two key components: area sources and active faults combined with background seismicity. The main features of the seismo-tectonic domains in the Caucasus region were summarized into three seismogenic classes (i.e. shallow crust, volcanic sources and deep seismicity). Given this classification, a set of ground motion prediction models was selected for each tectonic region and used to quantify the inherent uncertainties of ground motion. The probabilistic seismic hazard was computed for the entire region using the OpenQuake engine; the results including mean and quantile hazard maps, hazard curves and hazard spectra. Comparisons with previous probabilistic seismic hazard maps, followed by a discussion and outlook, conclude the paper.KeywordsGeorgiaEarthquakeSeismogenic sourcesSeismic hazard