Analysis of Active Tectonics of Chahak Fault Zone (Northwest of Birjand - East of Iran)

The study area is located 80 km northwest of Birjand, the central of Southern Khorasan province, and is located in the structural province of Sistan and part of North Lut. To study the amount of tectonic activity in different parts of the study area resulting from the activity of the well fault zone, study and study of tectonic morphology indices can be a good tool to achieve this goal, in this study of tectonic morphology indices such as shape coefficient Basin (Ff), drainage density (Dd), asymmetry of the drainage basin (Af) and river channel sinusitis (S) as well as field evidence of use. After calculating the indices in each sub-basin in accordance with the faults of the region, the amount of tectonic activity was obtained. Then, for each index, a zoning map of the tectonic activity level in different parts of the study area was drawn, and finally, the relative active tectonics index (IAT) was calculated to determine the total tectonic activity level, which according to the average The study area was divided into 4 categories of very high, high, medium and low tectonic activity, which measured indices in the basin corresponding to the eastern branch of Chahak fault show higher values that indicate high activity of Chahak fault In this section.