Hydrological Processes on the Karak Plateau
Dr. Mark Green
Karak Plateau east of the Lisan Peninsula
The Karak Plateau is located along the western border of Central Jordan adjacent to the Dead Sea. The plateau is a classic upland landform, dissected by the large canyons. Images from space vividly illustrate why this region is called a plateau, even by those unfamiliar with geomorphological terminology.
Of the many geomorphological “topics” that could be explored on the Plateau, the focus of this study is the hydrological processes at work on the plateau. A first glance at the plateau raises the initial question of how to account for such enormous channels (i.e., canyons) in an environment that for at least the past 4,000 years has received no more than 340 mm of annual precipitation. Drought conditions in recent years have often reduced annual precipitation to no more than 200 mm. However, a closer look at the topography of the plateau reveals yet another characteristic that must be incorporated into any discussion of the plateau. When we look at the modern gradient of the plateau surface, we discover that the overall slope of the Plateau surface is opposite of the canyons that carry runoff into the Dead Sea.
Profile of the Karak Plateau looking northward from Wadi Hasa
The result is that we have a plateau, with annual precipitation of around 300mm, being drained by huge canyons (nearly ¾ mile deep and over a mile wide) that drain the opposite direction of the surface gradient of the plateau.
In order to understand the landform we see today, we must go back a few years, as it turns out, around 130 million years. The present appearance of the Karak Plateau, like many landforms across the earth, owes much to morphologies that are inherited. For discussions on inherited landforms see Abrahams, 1984; Melton, 1958; Oberlander, 1965; and Smith, 1994.