Active Tectonics of the Saymareh-Karkheh River Basin (Northwest of Persian Gulf, Iran)

Abstract

Active tectonics is an indicator of recent movement of mountains and landscapes evolution for regions affected by current tectonic activity. The Saymareh-Karkheh river basin is located on the Zagros Mountain in the west Iran. The Zagros Mountain is an orogenic belt that is formed by the collision between the Eurasian and Arabian plates during Cenozoic. Active tectonics has analyzed by measurement of six geomorphic indices (hypsometric integral, basin asymmetry factor, basin shape, the stream length-gradient, mountain-front sinuosity and valley floor width-height ratio) which they combined to index of active tectonics (Iat). Based on values of this index, the Saymareh-Karkheh river basin was divided into high (Class 2, 18.8%), moderate (Class 3, 70.3%), and low (Class 4, 10.9%) relative tectonic activity parts. The above results confirm the usefulness of geomorphic analyses for regional assessment of active tectonics they are compatible with differential tectonic activity in the High Zagros and Zagros fold and thrust belt. Also, it was revealed that geomorphic indices and using of GIS technics are very useful to investigation of active tectonics in the mountain areas.