MORPHOMETRIC ANALYSIS OF MAIN DRAINAGE BASINS IN THE ZURBATIYAH VICINITY, EASTERN IRAQ

Abstract

The study area covers about 5600 Km2 comprising three main watersheds; Torsaq, Shosharin and Badrah. It is built up of sedimentary formations (Oligocene – Pliocene) beside various types of Quaternary sediments. Different morphometric parameters are computed in this study using Geographical Information system (GIS) and Remote sensing techniques through the ease of uses of high resolution Digital Elevation Models (DEMs). The highest stream order of the studied basins is 6th order. The drainage density analysis indicates medium value suggesting coarse to moderate drainage texture. The values of bifurcation ratio range from 2.2 to 11. The values of form factor and circulatory ratio indicate that the studied basins are elongated in shape. According to dissection index value, the overall basins are moderately dissected; however the upper parts of the basins, which are located within the Zagros Fold-Thrust Belt, are characterized by their high tectonic activity, whereas their lower parts, located within the Mesopotamian Zone, are characterized by low tectonic activity.