الفهرس 
Seismotectonics of Sinai Peninsula, Egypt and Their Implicationsfor Seismic Hazard Evaluation
direction of the bounding faults of the Aragonese deep. Zones A and B matchOnly 14 pages are availabe for public view
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Abstract
A comprehensive study of the seismotectonics of the Sinai subplate and their relations to the regional plate tectonics were conducted. Their seismic hazard implications for Egypt were studied also. Seismicity in the northernmost part of the Red Sea has been studied. Three programs for hypocetral location were used to relocate earthquakes. Vp/Vs value is estimated using Wadati diagram with an average ratio of 1.74. For the data set from 1995 to 1999 the average epicentral and focal depth errors are <U+2264> 2 km while the RMS is <U+2264> 0.2 for the majority of the studied events. A complete and true picture for the seismicity of the area was obtained. The triple junction nature controls the activity in this area. Duration magnitude (MD) is compared with the ML published by the National Earthquake Information Center (NEIC). The relation between ML and MD is approximated by: ML (NEIC) = 1.0256 MD (HSN) + 0.297. Individuals and composites focal solutions of many events were made. Results indicate that the motion along the Levant trend is mainly strikeslip with some extensions along the pullapart basins of that trend. The motion along the southern part of the Gulf of Suez is mainly extensional. The strikeslip component appears along the middle and the northern part of the Suez Gulf. The earthquakes mechanisms in Ras Mohammed region are affected by the two gulfs trends and the thermal activity of the region. Focal solutions along the Cyprus Arc reflect the subduction process of Africa including Sinai under Eurasia, the bending of the subducted slab, and the difference in convergence rates at the Hellenic and Cyprus Arcs and/or the westward movement of the Anatolian plate. The seismotectonics of Sinai subplate reflect the ongoing breakup process of the southern part of the Suez Rift but the ambiguity of the northern extension of the Suez Rift towards the Nile Delta still occur. The probabilistic seismic hazard analysis approach was applied to assess the seismic hazard in Egypt. The maximum expected moment magnitude for Egypt is 7.8 and the estimated bvalue is less than one. The maximum expected peak ground acceleration in the next 100 years with a probability of exceedance 10% is 0.21 and is suggested to be released along the Levant trend and Aswan area. The preliminary seismic hazard zoning maps reveal that Egypt is a country of low to moderate seismic hazard.