Investigating the Geomorphic Evidence and Movement Potential of Active Faults in Golpayegan Area, Iran

Abstract

Along the western part of Golpayegan city, in an area parallel to the main axis of Zagros, the calculation of morphometric indices in the Golpayegan basin means that the tectonic activity is significant from a morphometric point of view. Tectonic activity was not the same throughout the region and although no major earthquake was reported in Golpayegan region, morphometric evidence shows the general tectonic activity of the region. Geomorphic evaluation of the Golpayegan area shows that some of the northwest-southeast trending faults and the tips of some faults in the west Golpayegan city should be considered as potential earthquake areas. The Golpayegan area is located in the Sanandaj-Sirjan structural zone, one of Iran’s most active seismic zones. The present study aimed to evaluate the effect of faults on landforms through morphotectonic indices and the causes of knick points and knick zones in the Bedrock Rivers in part of the Sanandaj-Sirjan tectonic zone. To this end, six morphometric indices such as longitudinal gradient (\(SL\)), hierarchical anomaly (\(\Delta a\)), the bifurcation index (\(R\)), hypsometric integral and hypsometric curve (Hi-Hc), relative relief (\(Bh\)), and basin shape (\(Bs\)) were calculated and analyzed in 22 sub-basins of the area. Based on the findings, the existence of slope-break knick points at the mountain piedmont and at the outlet of large rivers through active faults demonstrated these landforms were created by movements along the main faults such as Bid Arab and Khansar faults which have the highest mobility potential.