The Geomorphology of Gravelly Bars in Wadi Ewhaideh –Jordan

Abstract

The study deals with the geomorphology of gravelly bars in Wadi Ewhaideh through the analysis of its morphological, sedimentary, and morphometric characteristics. The study also aims at determining the extent to which the phenomenon of gravelly bars spreads alongside the Valley, and the impact of the different water characteristics of the stream in determining their morphometric characteristics.

The study relied in its methodology on remote sensing techniques through the analysis of (1-25000) - scale - aerial photographs for the year 2011.  The remote sensing techniques were used to analyze the morphometric dimensions of gravelly bars and their geographical distribution areas, then matching the results of the analysis of aerial photographs with the field results.

The study found that the evolution and growth process of gravelly bars are associated with two variables, namely: the amount of sediment carried by the river flows and deposited above the gravel accumulation which forms the body of the gravelly bar; while the second variable is represented by the capability of the body of the gravelly bar to resist the water shear forces caused by water currents when colliding with it.

The study also showed that the loose banks of the river directly affected the sedimentary characteristics of the gravelly bars, as the deposits of the bars in those areas are characterized by coarseness and increased sizes rate, where their average size rate reached (29.5 mm).

Keywords: Gravelly bars, Wadi Ewhaideh, remote sensing, fluvial processes, sedimentary characteristics.