Application of the cross-flow angle (CA) index in analysis tectonic geomorphologic in Northeastern watersheds of Iran

It is very important to use geomorphometric indices to detect active tectonics. The parameters related to the drainage network are the angle of connection of the rivers. And quantitative assessment can help to identify the active tectonics, earth science researchers. Kopet Dagh -Hezarmasjed Geological Unit and Aladagh - Binalood is one of the most active geological units in Iran. In this research four basins were selected to evaluate the role of tectonics in the cross-flow angle of the rivers.Baghrood and Bojan Basin in Aladagh-Binalood Zone and Zavin and Sharrood Basins in Kopet Dagh -Hezarmasjed Construction Zone .In this way, were used cross-flow angle (CA), branching index (R), basin asymmetric percentage index (PAF) and mountain front elevation index (Smf).Also, cross-flow angle calculation showed that the highest amount in Zavin watershed is 73/67 degrees and the lowest amount in Baghrood Basin is 59.5 degrees.Which indicates changes in the flow paths of the streams, such as the capture of the river and, consequently, tectonic movements in the slope Khor anticline.Also, the calculated values of (R) (Smf) and (PAF) indicate that most tectonic species of Kopet Dagh basins are compared to the Binalod mountain basins.