EXPLORATION OF THE DUNES

About 4 km inland from Sealine, we catch the desert "fast lane" made up of hundreds of tire tracks all heading in roughly the same southerly direction, and from there we go straight for about 20 km to a very wide basin (GPS point: N24°41'44 E51°24'57) where we can see a few buildings. Our final Gps point indicated above corresponds to the nearest "sea", 5 km away. Following the track, we keep going south, find a rusty signpost and turn right towards the intermediate point N24°39'19.42 E51°24'18.56. Here we are. The coast opposite is in Saudi Arabia, with the border running through the middle of the inlet. Those familiar with the area will of course know of dozens of more remote spots, stretching 20 km to the west. The point N24°36'39.8 E51°21'16.8 corresponds to the summit of a large dune offering a panoramic view of the Khor Al Udayd.

The Barkhane is a crescent-shaped dune, convex in the wind. Its migration speed depends on its size and the slope on which it moves, decreasing as its size increases. In the Sahara, people used them as safes: they would hide something on the leeward side and the parcel would reappear a few months later on the other side, the dune having passed over it! Barkhanes don't usually remain isolated. They can merge to form more or less complex ensembles, ranging from barkhanic chains or trains to veritable dune massifs.

A parabolic dune is an asymmetrical horseshoe-shaped dune with a windward concavity, often more or less fixed by vegetation. Its arrangement in relation to the wind direction is the reverse of that of the barkhane. The parabolic dune is not very mobile and generally does not migrate much once it has formed.

Pyramid dunes or "ghourds" are sand hills often in the shape of a star-shaped pyramid with three or more arms spreading out from the top. Up to 300 meters high, these dunes signify the absence of prevailing winds. The ghourds can be aligned to form ghourdique chains.

Singing sand dunes. You and your guide pass through the "singing dunes". You walk down the open gates of the "singing dune" at slow speed, and indeed you hear a rather strange grinding noise that occurs nowhere else in this desert. It's due to vibrations, but we don't know exactly why or how. How strange!