An Updated Seismic Hazards and Seismotectonic Studies for Sinai Peninsula, Egypt

Sinai Peninsula is located in western Asia in northeastern Egypt. It is characterized by its numerous mineral resources such as gold, copper, lead, zinc, tungsten, molybdenum, manganese, limestone, gypsum, iron oxides, sand, gravel, feldspar, kaolin and marble, which is used in many industrial raw materials such as metallurgy, cement and ceramic industries. Sinai's coasts are characterized by the presence of ultra-pure white sand as well as black sand deposits rich in titanium, zircon, manazite, rutile and garnet minerals. Sinai also has many coal, hydrocarbon, uranium and thorium resources. In south Sinai, the red sea bifurcates into the Gulfs of Suez and Aqaba, which are characterized by moderate to high seismic activity and the presence of earthquake swarms. To preserve mineral and petroleum reserves, protect facilities and installations, and eliminate any potential human losses, the seismic hazard in Sinai is evaluated using the probabilistic and deterministic seismic hazard assessment techniques. The historical and recent earthquakes were collected into a complete homogenous catalog and the study area was divided into 39 seismic sources plus a background seismic source according to seismicity, focal mechanism and tectonics to build a seismotectonic source model taking into account the impact of local and regional seismicity on Sinai. The recurrence parameters were estimated for each source and alternative attenuation relationships were used to account for epistemic uncertainty. Hazard maps were created to indicate the ground motion for peak acceleration and 0.1, 0.2 and 2 seconds-spectral accelerations. The probabilistic hazard maps were created to show ground motion at the 475-years return period while the deterministic maps show acceleration at the 50th percentile level for the selected probabilities of exceedance. Uniform hazard spectra and deaggregation of hazards were estimated for some cities in Sinai. Some earthquakes were simulated to study the effect of magnitude and distance to some cities on acceleration values. Synthetic accelerograms have also been created to assist earthquake eengineers in performing nonlinear dynamic analysis of buildings. The results of this study are very important in seismic risk assessment, microzonation and engineering studies.