Amazing Aorounga Crater, Chad
Amazing Aorounga Crater, Chad This image from Japan’s ALOS satellite shows the Aorounga Crater in northern Chad.
The crater is just south of the Tibesti Mountains, a range of inactive – with some potentially active – volcanoes in the central Sahara desert.
Measuring about 12 km across, the crater was created by a meteorite impact about 340 million years ago.
Clearly visible is the dark, central peak, caused by material splashing up after the impact, similar to how water bounces back up when a stone is thrown in. This mountain is surrounded by a flat, sand-filled ring, which is surrounded by another ring of rock from when the material was thrown outwards.
A distinctive low, sand-filled trough circles the others – the outer edges of the initial impact. The Aorounga Crater is an impact crater located in northernChad just south of the Tibesti Mountains in the central Sahara desert. Measuring 12 kilometers across
The linear rock ridges that run diagonally across this image are ‘yardangs’ and are formed by wind erosion. Here, we can clearly see how the wind blows from northeast to southwest. Sand dunes form in the wind-cut valleys between the rock ridges of the yardangs.
Linear rock ridges alternating with light orange sand deposits cross the image from upper left to lower right; these are called yardangs by geomorphologists. Yardangs form by wind erosion of exposed rock layers in a unidirectional wind field. The wind blows from the north-east at Aorounga, and sand dunes formed between the yardangs are actively migrating to the south-west. The circular Aorounga Impact Crater lies approximately 110 kilometers.
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