Navels land (16 photos)

Uh ... Cool.
 - This Diamond Mine Diavik





























And this - the structure Guell-Air Richat located in the Sahara Desert in Mauritania, well visible from space thanks to its huge size - its diameter is about 50 kilometers. The time of the most ancient ring - 0, 5-0, 6 billion years ago.
Once the structure was considered Richat impact crater, but this hypothesis is not consistent with the shape of a flat bottom and a complete lack of rock with traces of impact. Structure formation Richat a result of a volcanic eruption also seems highly unlikely due to the lack of a dome of igneous or volcanic rock. Most researchers are inclined to believe the layered sedimentary rock structures Richat result of erosion on the lifting portion of the earth's crust. As for the almost perfectly round shape structure Richat, its origin still remains a mystery.
All versions about the origin Guell-Air Richat still remain hypotheses.







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