Scientific Quarterly Journal of Geosciences

Scientific Quarterly Journal of Geosciences

Calculation and Interpretation of Some Morphotectonic Indices Around the Torud Fault, South of Damghan

Document Type : Original Research Paper

Author
M. Khademi
Damghan University of Basic Sciences, Damghan, Iran.
10.22071/gsj.2010.55433
Abstract
The only geologic evidence of the neotectonic activity of theTorud region is its seismisity which assumed to be related to the Torud seismogenic fault. This fault has been overlain by the Quaternary alluvium in the major part of its length. Therefore, the study of morphotectonical characteristics of the region gives more evidences about its activity. Calculation of three morphotectonic indices including stream length – gradient   ( SL) and ratio of valley – floor width to valley height (Vf) of stream channels and mountain front sinuosity (Smf) shows high SL values  (425 – 1044) and low Vf (2.68 – 3.34) and Smf (1.05 – 1.44) values and  indicate that  the region has activity specially at two parts: central part (near the mountain front ) and northwestern part ( near the main divide of the Torud mountains)  and therefore the tectonic activity class of the region can be number 1. The activity of the central part can be due to the movements of the Torud fault. The activity of the northwestern part is the result of the uplift of the region which is related to the at least one fault parallel with the Torud fault that has formed the relic mountain fronts at recent past. The distribution of strain of this activity shows the progressive deformation from north northwest to south southeast and from west to east.
 
Keywords
The Torud Fault
Morphotectonics
Neotectonics
SL
Vf and Smf Indices
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Scientific Quarterly Journal of Geosciences
Volume 19, Issue 75
Winter 2010
Pages 47-56