HYPSOMETRIC ANALYSIS OF AL-ADHAIM BASIN USING A NEW GIS- TECHNIQUE
Al-Adhaim dam basin is extended across the boundaries of Salahuddin, Kirkuk, and Sulaymaniyah provinces in the northern part of Iraq, covering an area of 11831 km2. The area is covered mainly in most upperparts by sedimentary rocks of the lower Eocene to Pliocene ages. The lower parts are occupied by sheet runoff deposits from the Quaternary age. The objectives of the current study are to carry out detailed measurements of hypsometric parameters to evaluate the degree of erosion conditions and to show the essential factors controlling the development of geomorphic stages in different parts of the basin. The analysis was carried out based on ASTER GDEM data using ArcGIS v10.6 hydrology toolbox and the morphometric toolbox and dividing the basin into fifteen sub-basins. The results show that the Al-Adhaim basin passes in the monadnock phase with a hypsometric integral of 19.02% and a highly concaved hypsometric curve. The sub-basins are classified into two groups of geomorphic stages, i.e., mature stage and Monadnock stage with hypsometric integral values between 18.4% and 34.6%. The results reveal the basin was controlled mainly by slopes, lineaments, Tertiary outcrops, Quaternary deposits, and hydrological soil groups B and D.