Tin Bider
Key facts
- Country
- Algeria
- Diameter
- 6 km
- Age
- less than about 70 million years
- Location
- 27.60° N, 5.12° E
Rings of eroded sedimentary rock about 6 km across in the Tinrhert plateau of the central Algerian Sahara, with a central uplift. It stands out clearly from the air.
Tin Bider is an eroded impact structure about 6 km across in the Sahara of central Algeria, on the Tinrhert plateau.
What can be seen. The structure has a central uplift of tilted and broken rock, surrounded by rings of ridges and valleys, carved by erosion from the deformed sedimentary layers. In the dry desert it is clearly visible on satellite images.
What it hit. The impactor struck a sequence of Cretaceous sedimentary rocks, including sandstones and limestones.
Proof of impact. Geologists found quartz grains with planar deformation features, the microscopic fingerprint of shock, which confirmed an impact.
Age. The youngest rocks affected are Late Cretaceous, so the impact happened less than about 70 million years ago. Its exact age is unknown.
Why it matters. Tin Bider is a fine example of a complex crater in layered sedimentary rock, with its central uplift exposed by erosion. The impactor is unknown.
Visiting. The structure lies in remote desert. Travel with local guides and carry plenty of water.
Did you know?
Tin Bider has a central uplift surrounded by rings of ridges.
It is clearly visible on satellite images of the Sahara.
The impact happened less than about 70 million years ago.