A new evaluation of seismic hazard for the northwestern part of Saudi Arabia

A new evaluation of seismic hazard in the northwestern part of Saudi Arabia area has been carried out, for the minimization and mitigation of earthquake losses. The study area controlled by a number of major regional tectonic features including the Red Sea, Gulf of Suez, and Gulf of Aqaba—Dead Sea fault system and a larger number of recorded earthquakes. A probabilistic seismic hazard analysis is performed within a logic-tree framework. The analysis started with an exhaustive revision of the seismic catalogues of the area and vicinity from which a catalogue has been declustered and homogenized at moment magnitude, M w . According to the tectonic setting and spatial distribution of earthquakes in area and vicinity, twelve seismic zones are defined. The seismic hazard parameters, namely the b-parameter (of the Gutenberg–Richter relation), M max (the upper-bound magnitude), and, λ (the annual rate of occurrence of earthquakes with minimum magnitude M min ≥ 3), are calculated for each seismic zone. The ground-motion prediction models have been selected according to the tectonic regime associated with the earthquakes in each source zone. The results are displayed in the form of contour maps of peak ground acceleration and five ground-motion spectral periods for a return period of 475 years. The maximum peak ground acceleration values are found around the Gulf of Aqaba and it is 325 gal for 475-year return period (equivalent to 90 % probability of non-exceedance in 50 years), while the lowest values in the eastern region is 75 gal. This is the first study developed at the northwestern part of Saudi Arabia in terms of peak ground acceleration and different spectral acceleration—SA (T). As a result, the new generation of maps will be useful in the revision of seismic codes of the area. Copyright Springer Science+Business Media Dordrecht 2013