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Overview:
Earthquakes are one of the most disastrous natural phenomena resulting from the movement of the solid lithosphere at the outer part of the earth. Large earthquakes can cause a number of serial disasters like landslides, horizontal and vertical displacements of active faults, fires, liquefaction, tsunami generation, loss of billions of dollars, and many indirect losses from job losses, disruption of investments, temporary loss of tourism revenues, etc. These disasters can cause severe losses as that caused by the as earthquakes. Among all earthquake hazards, the earth's shaking is the most serious, causing the fall of objects and the collapse of installations partially or completely.
Although earthquakes cannot be stopped or predicted so far, their devastating effects can be mitigated by pre-emptive action involving the efforts of authorities, scientists and citizens. The majority of scientists agreed that the best way to reduce the effects of earthquakes is to properly assess seismic hazards and provide results to decision-makers, regulators, rescuers and听 agencies so that seismic forces can be designed and built to withstand earthquake forces, and to facilitate the development of contingency and rescue plans. In this regard, the Earthquake Monitoring Center research group at Sultan Qaboos University will carry out an assessment of the seismic hazards at the bedrocks of all the Sultanate's cities and results of these studies to be disseminated to public. These studies will be the basis for the preparation of a preliminary building code for the resistance of seismic forces, which can be relied on and continuously developed for the study and design of buildings in the Sultanate.
It should be noted that, during the earthquake, soft soils can amplify the shakings of the structures and make them last longer, thereby increasing damage to the built-up installations. For example, the Mexico City earthquake in 1985, which occurred 400 km from the city center, where the soft soil under the city to enlarge the movement of the ground and make it shaking enough to cause the collapse of many buildings of medium height. This destruction indicates the possibility of having a significant damage to sites with weak soil even at long distances from the earthquake location. Therefore, proper seismic hazard evaluation requires not only a proper assessment of the seismic hazard at bedrocks, but also computation of the impact of the soil on the ground motion and add its effect to the ground-motion at the bedrocks. Because the nature of soils may vary from site to another within a short distance, it is necessary to evaluate its effects on ground motion in close distances so that we can draw maps for the geographical variation of the amplification values and the values of the ground-motion, and the location where it is expected to be most destructive. These studies have been carried out in the Governorate of Muscat and the Earthquake Monitoring Research Center hopes to complete these studies for all the governorates of the Sultanate, especially the North, as they are more vulnerable to earthquakes because they are closer to Makran and Zagros seismic zones.
It should be noted that these studies are an important part of the Sultanate's efforts to establish an integrated system for the management and control of seismic hazards to ensure the mitigation of its effects and ensure the safety of the Sultanate's infrastructure. Despite the limited seismic activity in the Sultanate, ambitious projects and rapid population growth require attention on seismic impacts, with the extreme risk of exposure to intense seismic activity from near or far seismic sources. Continuous monitoring will ensure the accurate mapping of all seismic sources and the continuous development of seismic hazard maps and provide an accurate map of seismic shaking in the event of an earthquake based on measurements, not only calculations and provide these measurements to the responsible authorities to support decision-makers in emergency situations. These instantaneous maps contribute to the identification of the most affected and the most vulnerable sites in a very short time. The construction of this integrated seismic monitoring system will assist decision-makers in the optimal use of land through the development of building codes and the development of necessary legislation and standards to avoid possible seismic risks in the development of areas and the issuance of building permits
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