Probabilistic Seismic Hazard Assessment in Northeast of Iran

In this paper, seismic hazard analysis is performed using probabilistic hazard assessment method in a region bounded between 35 to 38 N and 57 to 61.5 E. First, the seismotectonic map of the region is provided using geological maps and earthquakes and micro-earthquakes catalog. Then, 8 Potential seismic sources were detected considering region’s tectonic, seismicity of the area and type of the faults. After that, seismicity parameters were evaluated.

Finally, taking into account these obtained parameters and applying appropriate attenuation relation using probabilistic method, peak ground acceleration from activity of sources around the site in Mashhad city for return periods of 50, 100, 200 and 475 year are evaluated and hazard assessment maps are depicted. Response spectra curves for all sources of a particular period has a peak in approximately 0.12 seconds. The obtained risk maps obviously show more risk for potential seismic sources 6 and 7 in every 4 mentioned return periods. Regarding the obtained results, with a sequential increase in return period, we could see that the increment of risk is gradually extended to the eastern part of the region.