Morphological Analysis of the Slopes on Both Sides of the Main Channel of Wadi Bou Msafir Basin Using a Digital Elevation Model and Slope Angle Tangent Calculation
DOI:
https://doi.org/10.58987/4me9qv69Keywords:
Morphological analysis, Trigonometry, Geographic information systems, Angle of slopeAbstract
This study aimed to measure the slopes of both sides of the main channel in the Bou Masfer watershed, using the Pythagorean theorem to calculate the tangent of the slope angle in a right triangle. This quantitative approach derives key morphological characteristics of both channel flanks via geographic information system (GIS) analysis of a digital elevation model (DEM). Twenty-one cross-sectional profiles were extracted along the main channel from a contour map derived from the DEM, with a vertical contour interval of 20 m and a 20 m spacing between consecutive sections. The objective was to highlight prominent slope forms, angles, and evolutionary stages, while generating precise measurements to expand the geomorphological database for the study area, A quantitative methodology was applied, involving morphological measurements of cross-sections and calculation of the tangent of the slope angle, complemented by descriptive-analytical methods to describe and analyze the studied cross sections. Key findings reveal symmetrical cross-sectional shapes due to homogeneous geological formations, with average opening widths converging at 319.2 m (right flank) and 315.7 m (left flank). Vertical incision dominates the main channel, reaching maximum depth as it traverses the steeply sloping initial edge. Average slope angles for both flanks approximate 13°, classifying them as moderately steep, indicative of an early youthful stage in the basin's geomorphic cycle.
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