Seismic moment rate and earthquake mean recurrence interval in the major tectonic boundaries around Oman

Owing to the short earthquake history, mathematical relationships were developed for calculating the earthquake recurrence from the rate of slip along the active faults. Based on the slip rate and the well-known Gutenberg-Richter law, various relationships between the earthquake occurrence parameters and the crustal deformation rates were developed. Among those is the widely used Molnar (1979 Bull. Seismol. Soc. Am. 69 115-33) mathematical expression, which is modified in the current study to produce a mathematical model based upon the truncated Gutenberg-Richter model instead of the normal Gutenberg-Richter one. The modified model is then tested and applied for the major tectonic boundaries around the Sultanate of Oman. The seismic moment rate is determined and the seismic hazard in terms of recurrence interval is expressed for the investigated regions. The calculated recurrence interval with moment magnitude 8.1 in the Makran zone is found to be 760 years, while for earthquakes with magnitude equal or greater than 5.8 in the Owen fracture zone is 4.904 years in consistency with the observed data. Recurrence intervals resulting from the original Molnar (1979) model and the current modified model were compared and discussed for the Zagros region.