Arabian Desert - Geology and Geography

Geology and Geography

Detailed geological features :

• A corridor of sandy terrain known as the ad-Dahna desert connects the large an-Nafud desert (65,000 km2 or 40,389 square mile) in the north of Saudi Arabia to the Rub' al-Khali in the south-east.
• the Tuwaiq escarpment is a region of 800 km (500 mi) arc of limestone cliffs, plateaux, and canyons.
• Brackish salt flats: the quicksands of Umm al Samim
• The Wahiba sands of Oman : an isolated sand sea bordering the east coast
• The Rub' al-Khali desert is a sedimentary basin elongated on a southwest to northeast axis across the Arabian shelf. At an altitude of 1,000 metres (3,300 ft), the rock landscapes yield the place to the ar-Ruba' Al-Khali, vast wide of sand of the Arabian desert, whose extreme southern point crosses the centre of Yemen. The sand overlies gravel or gypsum plains and the dunes reach maximum heights of up to 250 m (820 ft). The sands are predominantly silicates, composed of 80 to 90% of quartz and the remainder feldspar, whose iron oxide-coated grains color the sands in orange, purple, and red.