Investigation of active tectonics of Alvand mountain using morphotectonic indices, Hamedan

Alvand granitoid pluton has penetrated into the metamorphic rocks of Sanandaj-Sirjan zone in the Middle Jurassic period and it has created an aura of contact metamorphism around it. Alvand granitoid pluton is the highest elevation in Hamedan region and Its catchment area is located in the south of Hamedan. In this study, the tectonic activity of catchments of Alvand Mountain has been studied based on geomorphic indices. According to the characteristics of the catchments, Asymmetry factor (Af), Hypostometric integral index (Hi), Stream length-gradient index (Sl), Mountain-front sinuosity (Smf), Valley floor width-to-height ratio (Vf), Basin Shap index (BS) and Transverse topographic symmetry index (T) has been studied and Finally, with the overlap of the obtained indices, the relative active tectonic map (IAT) of the region was determined. The values obtained for active tectonics show that the area has three zones with high tectonic activity, medium tectonic activity and finally low tectonic activity. Northeast and east of Alvand mountain shows high tectonic activity compared to other parts and There are large reverse faults with northwest-southeast striking. Existence of many new landslides in this area indicates high tectonic activity