Investigation of new construction of caravanserai fault zone based on morphological and tectonic patterns prevailing in North Nobaran, northwestern Iran

The Karvansara fault zone is located in north of the Nobaran and in the Central Iran geological and structural zone. This zone is located at the south of the Caspian Seawithin the Alpine-Himalayan belt.The aim of this study is investigation of the morphological evidences and evaluation of the relative tectonic activities along Karvansara fault zone. For this purpose, in this study, five morphometric indices including drainage basin asymmetry factor (Af), transverse topographic symmetry factor (T), stream length–gradient index (SL), ratio of valley floor width to valley height (Vf) and hypsometric integral index (Hi) as well as fractal dimensions of faults and drainage network have been calculated. Assessment of these indexes and the overlap of their results with each other and evaluation of the index of relative tectonic activity (IAT) show that most of the study area indicate very active to active classes of the relative tectonic activity. Also, calculation the fractal dimension in eleven boxes in the study area for the faults and drainage network by square method, drawing of the log-log diagrams and the use of relevant fractal analysis show the tectonic activity of the region. The neotectonic study of the Karvansara fault zone and the location of the basins with moderate to high tectonic activity, along the major active fault zones, especially in areas where fracture density is higher than other regions and fractal dimensions calculated for the fault zone and drainage network indicate activity of the fault system is on the southern part of the study area.