Eye of The Sahara

Located in Mauritania, the Eye of the Sahara also known as the Richat Structure is a huge circular formation; it was originally thought to be a crater. It has been studied by numerous geologists. And for a while, scientists did think that the Eye of the Sahara was an impact crater. But they didn't find enough melted rock to make that guess hold water. Current theories suggest a much more complicated story behind this incredible natural formation but the more recent and accepted theories suggest that it is, in fact, a product of erosion that took place in geological time.

Two Canadian geologists think that the Eye's formation began more than 100 million years ago, as the super-continent Pangaea was ripped apart by plate tectonics and what are now Africa and South America were being torn away from each other.

Molten rock pushed up toward the surface but didn't make it all the way, creating a dome of rock layers, like a very large pimple. This also created fault lines circling and crossing the Eye. The molten rock also dissolved limestone near the center of the Eye, which collapsed to form a special type of rock called breccia.

 

A little after 100 million years ago, the Eye erupted violently. That collapsed the bubble partway, and erosion did the rest of the work to create the Eye of the Sahara that we know today. The rings are made of different types of rock that erode at different speeds. The paler circle near the center of the Eye is volcanic rock created during that explosion.

The main ring structure of the Eye is the eroded remains of what was once a dome of layers of Earth's crust.

According to zmescience, “The Richat structure (Sahara, Mauritania) appears as a large dome at least 40 km in diameter within a Late Proterozoic to Ordovician sequence. Erosion has created circular cuestas represented by three nested rings dipping outward from the structure. The center of the structure consists of a limestone-dolomite shelf that encloses a kilometer-scale siliceous breccia and is intruded by basaltic ring dikes, kimberlitic intrusions, and alkaline volcanic rocks”

Some people believe that the Eye of the Sahara is actually the remains of the city of Atlantis, which Plato described as concentric rings of water and land.

Sources:

http://www.businessinsider.com/the-eye-of-the-sahara-is-still-a-mystery-2016-7?r=UK&IR=T

https://en.wikipedia.org/wiki/Richat_Structure

http://www.zmescience.com/science/geology/the-eye-of-the-sahara-05102010/

Pic Source:

https://en.wikipedia.org/wiki/File:Richat_Structure_-_SRTM.jpg