Investigation of seismic parameters, calculation of Seismic moment and Geologic moment Kopeh-Dagh zone in Northeast of Iran

Abstract

The Kopeh-Dagh zone is the northern deformation zone due to the convergence of the Arabian and Eurasian plates Which forms an active area with a northwest-southeast trend. Since old construction in the Bojnourd city, which is one of the most populous cities in this area, have over 50 years, and some of the historical and religious buildings ​​have their importance, and due to the presence of large earthquakes in the background seismicity of the zone, the necessity of the study is obvious. The aim of this study is to provide the seismiogenic layer maps, seismic hazard zoning map and Estimate of rate geologic moment and seismic moment In order to provide basic information for recognition and large-scale planning of the study area and to obtain clear information about the seismic hazard situation. According to the deep seismic map of the seismiogenic layer, To focus the depth of the seismiogenic layer along the reverse faults of the Kopeh-Dagh zone creates an angle of about 45 degrees. In the western part of this zone, reverse faulting and strike-slip faulting are not evident, , but there are seismicity. That could in the future be the result of a new shear zone in the area. By investigation of seismic parameters, Maximum average horizontal acceleration on the Bojnourd city resulted from Qhorlogh fault with seismic potential of 6.4 Richter 0.7338 g; This is when the fault is located about 2.34 km from Bojnourd city. Finally, according to the estimated PGA, the seismic hazard zoning map using Geostatistical Analyst tool in ArcGis software was plotted. In the study area, geologic moment average rate (3/48151E+17 Nm/yr) and seismic moment average rate ("1/1597E"×"14" Nm/Y)were estimated

Keywords

• geologic moment
• seismic moment
• seismiogenic layer
• seismic parameters
• kopeh-dagh zone