Evaluation and analysis of Tectonic Activities in Sivand Basin area using Morphometric Indices

Morphometry can be defined as a quantitative measurement of the shape of landscapes on the ground, which can be used to identify areas with active tectonics. The purpose of this research is to investigate the active tectonics in the Sivand basin using five morphometric indices of Asymmetry factor of the drainage basin (Af), Relative relief (Bh), Form factor (Ff), Hypsometric integral and curve (Hi) and Stream gradient index (SL). By conducting this research, it is possible to understand the active processes in the Sivand basin and prevent damages caused by natural disasters such as floods and earthquakes to some extent.

This is a survey carried out in 2022-2023 in Fars province and it is a practical study in terms of its purpose. The nature of the data and their calculations are quantitative. GIS software and digital elevation map (DEM) with an accuracy of 30 meters, were used to calculate the indices. For each index, a zoning map was prepared in the area, and each of the mentioned indices was classified into five categories very high, high, medium, low and very low geotechnical activity. Finally, by averaging the entire category of indices, a final index of relative active tectonics index (Iat) was obtained and the area was classified into three categories of high, medium and low terraforming activity.

In the sub-basins of Avanjan Fault, Musakhani Fault, Sivand Fault, Sivand river Fault and the faults located in the south of the investigated area, the measured indices showed high and medium values, which is due to the medium to high tectonic activity of the area.

The Sivand basin has medium to high tectonic activity and the northern, northwestern, middle and southern parts of the region are more active than other parts. It is due to the effect of the mentioned faults on the region.