Updated Seismic Hazard Curves, Maps, and Spectra for the Northern Dominican Republic using a Probabilistic Seismic Hazard Analysis

Abstract

Abstract This article presents updated seismic hazard curves, maps, and spectra of ground motion intensity parameters for the northern region of the Dominican Republic (DR) obtained using a probabilistic seismic hazard analysis (PSHA). The analysis uses as input data an earthquake recurrence model based on fault slip rates derived from GPS measurements published in the aftermath of the 2010 Haiti Earthquake. The seismicity rates data is used to calibrate a composite characteristic earthquake model, which is combined with a Poisson process to provide a temporal characterization of earthquakes occurrence. The PSHA accounts for uncertainties in the analysis by modeling magnitude and site-to-rupture distance as random variables, considering the aleatory uncertainty associated to the ground motion prediction equations (GMPE) used for spatial characterization of earthquake-induced ground motions. The seismic hazard curves and maps include (horizontal) peak ground acceleration and pseudo-spectral response accelerations at 0.2s and 1.0s periods for 5% damping and firm rock sites. The results show that the ground motion parameters with a 2% probability of exceedance (PE) in 50 years determined in this study are up to 46% larger than the corresponding parameters specified in the current DR building code for the northern DR. Moreover, the design response spectra for a site in the city of Santiago specified in the code is significantly lower than the 2% PE in 50 years uniform hazard spectra determined in this study for periods smaller than 0.5s, a range that includes the majority of the structures that define the built environment of the DR.