ABSTRACT
Kashaf rud river is located in border
zone of East Alborz and Kopet Dagh physiographic provinces in the north east
Iran. Geomorphic indices are useful tools to show the neotectonic regimes.
These indices have got the advantage of being calculated from Arc GIS and
remote sensing packages over large area as a useful tool to identify geomorphic
anomalies possibly related to active tectonics. In this research, seven
geomorphic indices (stream-gradient index, valley floor width-valley height
ratio, mountain-front sinuosity, drainage basin asymmetry, hypsometric
integral, drainage basin shape and transverse topographic symmetry factor) were
calculated along the Kashaf rud river. Then, based on a new index or modified
index of active tectonics (Miat) values that calculated by average of seven
geomorphic indices, relative tectonic activities levels were revealed. The low
class of Miat is mainly in the sub-basins of No. 6, 10, 13, 14, 21, 22, 23, 24 &
28 while the rest of the study area has moderate tectonic activities in the
other sub-basins. Our results show that the moderate value has located along
faulted area, which shows 2 class of relative tectonic activity. These faults
have been formed above an old suture zone between Cimmerian and Eurasian
plates.