Seismicity and Seismic Hazard Studies in Oman

The seismicity of a region is an essential input for any seismic hazard assessment, regardless of the approach adopted. Seismicity is a subject of continuous updating and additions of new events. The aim is to encompass all earthquakes generated from any seismic source that has the potential to generate significant hazards for the Sultanate of Oman. Therefore, a catalogue covering Oman and its surroundings was compiled from various local, regional, and international databases. Duplicated events from different databases were recognized and removed, and the most reliable earthquake parameters were introduced into the current catalogue. Priority was given to moment magnitudes (Mw) over other magnitude scales and introduced to the catalogue with their references. To ensure consistency, earthquakes with magnitudes measured on different scales were converted to moment magnitude (Mw) using empirical relationships. The seismotectonic activity of the area was reviewed and a special attention was paid toward the local seismicity of Oman whether historical or instrumentally recorded ones. During the last two decades, some seismic hazard studies were conducted for Oman, mostly in terms of response spectrum for 10% and 2% probability of exceedance in 50 years. Results of recent studies show slight differences in the obtained hazard values, particularly those conducted in the last 15 years. This could be attributed to the absence of considerable events inside or near the sultanate and most of them are conducted by the same research group. Additionally, no much change neither in the seismic source model nor the used ground-motion prediction equations attributed also to the minor variation in the hazard results, despite an updated earthquake catalogue is used.