What is the Richat Structure?

38 kilometres (23 miles) in circumference and located in the country of Mauritania in the Sahara desert, the Richat structure is a natural phenomenon. Also known as the ‘Eye of the Sahara’ or ‘Eye of Africa’ it can be seen from space and is in the shape of a bull’s eye. But what created this oddity?

The structure was believed to have been formed from an asteroid or meteor collision. However, recent study has decreed that it may instead be a symmetrical geologic dome formed after a dome collapsed due to high levels of erosion. Containing igneous, sedimentary and metamorphic rock, the rock is too ordered to be from a strike from outer space. An anticline formation, the rock gets younger as you go away from the centre with ages ranging from the Late Proterozoic era (approx. 600 million years ago) to the Ordovician era (around 400 million years ago). Completely unique, experts are still unsure on why it is almost completely circular in shape.