Richat Structure: A Geologic Wonder

Caitlin Dempsey


The Richat Structure, a geologic wonder viewable from space, is a striking circular feature found in the Sahara Desert in Mauritania.  Also known as the Eye of the Sahara, the structure measures 40 kilometers (roughly 25 miles) in diameter.  It was originally though to have been caused by a meteor strike, but scientists now believe it was formed by a large dome of molten rock uplifting and shaped by the forces of water and wind.  

A geologic dome, the Richat Structure has concentric bands of resistant quartzite rocks which form the ridges.  Sedimentary rock is found between the ridges.  

The magnificence of this natural phenomenon was captured on November 23, 2010 by the Advanced Visible and Near Infrared Radiometer on Japan’s ALOS satellite.  The image shows the Adrar plateau on the left side with darker sedimentary rocks.  The lower portion of the images shows the erg (sand dunes).  Despite the dry and inhospitable look of this region of the Sahara Desert the southern part of the Richat Structure shows the presence of vegetation in the form of trees and bushes as well as temporary lakes; a result of the rainy season that occurred a few weeks before the picture was captured.

Richat structure
Richat structure, Mauritania. Source: JAXA/ESA. Higher Resolution file (jpg).


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About the author
Caitlin Dempsey
Caitlin Dempsey is the editor of Geography Realm and holds a master's degree in Geography from UCLA as well as a Master of Library and Information Science (MLIS) from SJSU.

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