Morphotectonic investigation of Talkhab and Tozlugol faults and formation of the Meyghan playa, Arak

Meyghan playa near Arak city is located at the boundary of the metamorphic zone of Sanandaj- Sirjan and Urmia-Bazman volcanic zone. Two main faults of Talkhab and Tozlugol (Tabarte) play a key role in the formation of this basin by right lateral movement with northwest - southeast trend. In this study, morphotectonic indices were investigated to study the tectonic activity of these two faults. The measured indices include altimeter integral index, asymmetry index, stream length gradient index and basin shape factor. Investigating the relative active tectonics using the above mentioned indicators shows that Arak region has a relatively moderate to high activity. Particularly, the region between the two Talkhab and Tozlugol faults is more active than the other regions. The graben of the Meyghan Desert is formed due to the activity of the Takhab and Thouzlugol faults during the Pleistocene by right lateral transpresion zone. The southwestern side of the lake is in accordance with the Tozlugol fault. It seems that according to the morphometric studies of this area, the activity of the Talkhab fault is more than the Tozlugol fault and plays an important role in the formation of the Meyghan playa.