Rocher de Sel ("Salt Rock"), known in

Arabic Arabic (, ' ; , ' or ) is a Semitic languages, Semitic language spoken primarily across the Arab world.Semitic languages: an international handbook / edited by Stefan Weninger; in collaboration with Geoffrey Khan, Michael P. Streck, Janet C ...

as Khanguet-el-Melah ("Parade of Salt"), is a large geological formation in the

Ouled Naïl Range The Ouled Naïl Range ( ar, سلسلة جبال أولاد نايل, french: Monts des Ouled Naïl) is a mountain range in Algeria, part of the Saharan Atlas of the greater Atlas Mountain System. The range is named after a confederation of nomadi ...

, near the town of

Djelfa Djelfa ( ar, الجلفة, link=no, al-Ǧilfah) is the capital city of Djelfa Province, Algeria and the site of ancient city and former bishopric Fallaba, which remains a Latin catholic titular see. It has a population of 490,248 (2018 census). T ...

. Rocher de Sel is composed of a mixture of

salt Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quantitie ...

and

clay Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4). Clays develop plasticity when wet, due to a molecular film of water surrounding the clay par ...

, and is nearly in diameter and tall. Due to its composition, Rocher de Sel is distinctly whitish-gray, and entirely barren of plant life. Rocher de Sel was formed when the earth's crust folded upwards, pushing a previously-buried layer of salt and clay upwards in a bulge. Later precipitation would erode the surface into its current scarred and furrowed state. It is unknown why the formation has not eroded completely, despite the susceptibility of its materials. It has been suggested that the clay repels the area's light rainfall before it can do much damage, or that the water becomes so saturated by salt that it quickly becomes unable to dissolve any more. Another theory states that the formation is still bulging upwards at a rate that almost matches the erosion.

References

Landforms of Algeria Djelfa Province {{Djelfa-geo-stub