The fossil fjords of Namibia
Today’s Image of the Day from NASA Earth Observatory features the desert landscape of northwestern Namibia in southwest Africa. The valleys that cut through the plateaus, which were once fjords filled with seawater, are extremely old and well preserved.
According to NASA, new research indicates that the valleys are ancient relics of a time long before dinosaurs walked the Earth – when Africa was close to the South Pole, still part of the supercontinent Gondwana, and covered with ice.
Eventually, the ice flow carved out long, narrow valleys that filled up with water and created fjords that have managed to persist for hundreds of millions of years. The area is so well preserved that scientists call it a “fossil glacial landscape.”
“One who looks at these valleys has a snapshot of what the fjords looked like 300 million years ago, except that the ice here has long disappeared,” said Pierre Dietrich, a scientist at University of Rennes.
“Large-scale glacial landforms such as fjords are usually thought to be transient features, prone to be rapidly erased over geological timescales, which was obviously not the case here. One might therefore ask: what will happen to the fjords of Greenland and Norway in a distant future?”
Image Credit: NASA Earth Observatory
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By Chrissy Sexton, Earth.com Staff Writer
