Proposing a novel geo-structural model for Torbat-e-Jam-Fariman plain (Northeast of Iran), based on Geomorphic indices calculation, conjugating the field evidences

There are various faults in northern and southern margins of Torbat-e-Jam-Fariman plain which show the probability of enormous earthquake in the future. In present study the geomorphic indices contain Asymmetry Function (A_f), Sinuosity of mountain front (Smf), Valley floor index (V_f), Hypsometric index (Hi), Mean Axial slope of channel index (MASC) and Drainage Basin Shape (Bs), have been utilized to determine the relative tectonic activity index (IAT) to recognize, eventually, the geo-structural model of the study area. Faults and folds control the geo-structural activities of the study area, and the geomorphic indices are being affected in consequence of their activities. The intensity of these activities is different throughout the plain. There are many geomorphic evidences, related to active transform fault which are detectable all over the study area such as deviated rivers, quaternary sediments transformation, fault traces. Therefore, recognition of geo-structural model of the study area is extremely vital. Field study, then, approved the results of geomorphic indices calculation in determining the geo-structural model of the study area. Results depicted that the geo-structural model of the study area is a kind of Horsetail splay form which is in accordance to the relative tectonic activity of the study area. Based on the above mentioned results it can be predicted that the splays are the trail of Neyshabour fault.