Probability analysis and Mapping Seismic Acceleration Scale in Lorestan Province by determining method

AbstractDue to geographical location, climatic conditions and geological situation, Iran is among the worst countries in the world in crisis conditions. Because it is located in seismic zones and has always witnessed devastating earthquakes, every year, due to natural disasters, losses and casualties enter the country. Undoubtedly, urban development, regardless of this phenomenon, will lead to more financial and life losses. Incomplete and sometimes inaccurate estimates of the maximum earthquake acceleration on the structure during its useful life are among the most important causes of damage to structures. Lorestan province, located in the west of the country, is of great importance due to its large population, historical and cultural significance and its location near the five active faults. Therefore, seismic probability assessment is considered necessary for the accurate estimation of possible earthquake parameters for the seismic design of the structure. For this reason, data were collected and refined such as fault profiles and earthquake catalogs for seismicity of the area. Using reductions and analytic relationships, we investigated the maximum horizontal acceleration in a 250km radius. Then earthquake zoning maps were provided for Lorestan province. The results show that most of the Lorestan province has a high probability level (PGA > 0.2g). The expected minimum acceleration in the region of 0.15g and a maximum of 0.701g is within the city of Dorud, which is not far from being conceivable because the region has suffered major Zagros earthquakes (earthquake 7.4 in 1909). The center of Lorestan province, Khorramabad city, is located in the area with a high probability level of about 0.3g. According to the results, it was found that the northwest strip to the southeast of the province, which includes the Oshtorinan, Borujerd, Dorud, Azna and parts of the Aligudarz, has the highest potential for earthquake hazard.