Tue, Jun 29, 2010
If an astronaut were to take a pause and may be look at the Sahara Desert of Mauritania, he or she would sure see a mysterious depression that could very well be mistaken for a very big eye! If you were to look at pictures or zoom in with Google earth, you would then see that the surrounding cliffs; make up the rest of the eye shape.
This strange phenomenon is actually a Richat structure (a prominent circular feature in the Sahara desert that resembles; most conspicuously; a bulls eye). It is all the more noticeable as the remaining expanse of desert is rather featureless. This structure was formed due to symmetrical uplifting of ‘underlying geology’. Hence, due to the thousands of years of erosion, this is visible now. However, this explanation is not accepted all over by the scientific community, as they believe that this Richat structure could also have been formed with a meteor impact.
Due to its significantly noticeable location and its wondrous shape, it has attracted attention since the earliest space missions. The eye has a diameter of about fifty kilometers (almost thirty miles)and its distinct bulls eye shape makes it very distinguishable. Six hundred million years old Paleozoic quartzite rocks in concentric bands; make the onion shaped formation. The white part of the eyes is a plateau made of sedimentary rock which stands about 200 meters above the desert surface.
The Richat structure fits as the iris and lies in a comfortable depression. The peak of the outer rim is almost five hundred meters above sea level. In the center, rocks that are resistant to weathering and erosion; form ridges that go up to hundred meters in height. The nonresistant rocks make the valleys. These features alternate and at the same time are concentric.
So how the circular formation came to be still remains a mystery.
If you are the type of person who like natures in her obscure and the bizarre form, then the ‘Eye of Africa’ is what you should be checking out. The structure has a gigantic appeal to it and seems more alive than just a Richat structure by itself ! For its- one in the world shape and geological importance. This Richat structure at the end of the day is what helps bring back our astronauts home !!