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Tag Archives: geology

175. The Great Saharan Eye

In a remote section of the Sahara Desert, Mauritania specifically, there lies this most mysterious formation, the ‘Eye of the Sahara,’ also known as the Richat Structure. Those passing over the large flat dome on the ground do not notice anything particularly out of the ordinary, but when viewed from space it stands out.

The eye of the Sahara is 50km in diameter and when viewed from above it does bear a resemblance to the human eye. Especially when one considers that it is actually a low dome, like a large eyeball peering out of the desert and gazing up into the sky. Its bizarre appearance and considerable size have led to great speculation as to how it ever came to exist. It used to be that no-one understood its formation and even now it has been extensively studied few believe that we are in possession of the truth yet. I suppose we shall have to wait, and see.

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Posted by on July 22, 2011 in Articles

 

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145. Death Valley’s Sailing Stones

In Death Valley, California, the stones move: nobody has figured out how. These are sailing stones. You can find them all in one area, just around the aptly name Racetrack Playa.

Here the valley is scored with flat tracks between 8 and 30cm wide, some curvaceous whilst others straight or jagged. Their marks score rarely more than 2 cm into the earth whilst their length range  from over 100 metres to and pitiful few centimetres. At the ends of each and every one, an unremarkable stone from one of the nearby towering cliffs. Without human or animal intervention the rocks have partially navigated the smooth valley floor. Bizarre.

These tracks are the cumulation of around 4 years work for each stone and its respective propulsion, whatsoever that may be. The mysterious force has been much researched but remains illusive, it makes the rough stones travel in jagged paths but lets the smooth ones wander aimlessly across the fragmented clay surface. No direction seems truly set, occasionally two adjacent rocks set out in parallel then one veers off wildly or even goes back the way it came.

The rocks are nothing special, or so it seems for the moment, the majority of the moving rocks are of the 260m high cliff nearby and made of Dolomite, a tough mineral mixture. Enthusiastically joined by some igneous rocks from the neighbouring cliffs in their wanderings of the Racetrack Playa.They weigh up to 40 kg at a time and even turn over, changing the width and structure of their paths.

This geological phenomenon is a true enigma, all suggested propulsions have been either totally wrong when tested or near negligible. The truth remains illusive.

 
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Posted by on June 14, 2011 in Articles, Trivia

 

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60. Stopping Niagara

Autumn 1969, the Niagara Falls shall crumble.

This was the prediction posited by the by the United States Engineering Corps. They believed that the constant rushing of the water was causing damage at the base of the cliff, making it unstable, and while they could deal with a very slow year on year retreat, they weren’t prepared for a large flood which would ensue if the cliff fell away in a large chunk. So they decided to perform a geological survey on the cliff face and perform any required maintenance work

But how does one work on a waterfall that is hurling 168,000 m3 of water over its top every minute?

The Army Corps of Engineering took the simplistic approach. The water was a problem – so they took away the water.

In an unprecedented move they de-watered the Niagara Falls, rerouting the water through a newly cut riverbed which allowed the water to rejoin the river further down. After this the cliff and several miles of river were left bone dry.

The Army Corps of Engineering, setting about... Engineering

Over the course of the next six months they cleared away debris from the base of the cliff and drilled some holes into the cliff to maintain a constant moisture level. They also set up a walkway.

A mere 20 feet away from the cliff face it became a great site for the tourists who wandered across with perplexed looks. Especially when they were allowed to amble down the dried out river bed.

The dry times had to come to an end and after installing some hydroelectric turbines at its base the Engineers decided to blow up their temporary dam and allow the water to flow once more.

To this day the Niagara Falls gallantly gush water day by day by day. Nothing has since impeded their flow. In this case, the mission was a success.

However thousands of tourists never saw and never will see the splendour of a dry Niagara Falls, one of the few modern day wonders.

 
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Posted by on March 20, 2011 in Articles, Trivia

 

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