Tenoumer is considered to be an impact crater in Mauritania.

Details

The crater is located in the western Sahara Desert. It is 1.9 km (1.2 mi) in diameter and its age was estimated to be 21,400 ± 9,700 years old but as of 2016, is thought to be ~1.57 Ma.

The crater is exposed at the surface and is nearly circular. Edges of the crater rise up to 110 m (360 ft) high above the base of the crater, but the bottom of the crater is covered with an approximately 200 to 300 m (660 to 980 ft) thick layer of sediments.

Tenoumer crater has formed in gneiss and granite of Precambrian peneplain with a thin layer of Pliocene sediments (no older). The crater is believed to be caused by an impact event due to basement rocks found outside the crater. A volcanic origin was once theorized because of the discovery of basalt and rhyodacite outside of the crater basin, but current evidence clearly indicates an impact origin.