Alps growing just as quickly in height, as they are shrinkingNovember 6th, 2009 - 1:40 pm ICT by ANI
Washington, November 6 (ANI): A group of German and Swiss geoscientists are on the verge of proving that the Alps are growing just as quickly in height, as they are shrinking.
Due to glaciers and rivers, about exactly the same amount of material is eroded from the Alp slopes as is regenerated from the deep Earth’s crust.
The climatic cycles of the glacial period in Europe over the past 2.5 million years have accelerated this erosion process.
Scientists have now proven that today’s uplifting of the Alps is driven by these strong climatic variations.
The formation of the Alps through the collision of the two continents Africa and Europe began about approximately 55 million years ago.
This led to the upthrusting of the highest European mountains, which probably already achieved its greatest height some millions of years ago.
At present, however, the Swiss Alps are no longer growing as a result of this tectonic process.
Swiss geodesists, who have already been measuring the Alps with highest accuracy for decades, have observed, however, that the Alp summits, as compared to low land, rise up to one millimetre per year.
Over millions of years, a considerable height would have to result.
But why then are the Alps not as high as the Himalayas?
Researchers from the GFZ German Research Centre for Geosciences were able to calculate that mountains eroded concurrently at almost exactly the same speed.
“This mountain erosion cannot even be determined using the highly precise methods of modern geodesy,” explained Professor Friedhelm v. Blanckenburg from the GFZ.
“We use the rare isotope Beryllium-10, which develops in the land surface via cosmic radiation. The quicker a surface erodes, the fewer isotopes of this type are present therein,” he added.
Therefore, von Blanckenburg, and the GFZ geoscientist, Dr. Hella Wittmann, have analysed this “cosmogenic” isotope in the sand of the Swiss Alps rivers and, thus, in the direct products of erosion.
As to how the Alps erode at the same speed that they rise, von Blanckenburg said, “Here pure upthrusting forces are at work. It is similar to an iceberg in the sea. If the top melts, the iceberg surfaces out of the water by almost the same share.”
Thus, this paradoxical situation with the Alps that through wind, water, glaciers and rock fall, they are being constantly finely eroded from the top but on the other hand, regenerated from the Earth’s mantle.
This phenomenon, even if already postulated theoretically has now been proven for a complete mountain range for the first time.
Thus, the Alps are constantly rising, although they have been deemed “dead” in a tectonic sense. (ANI)
- Vast farming projects eroding earth's surface - Sep 04, 2009
- Rivers cut deep notches in Swiss Alps' broad glacial valleys: Study - Dec 06, 2010
- Humans causing erosion comparable to world's largest rivers and glaciers - Sep 03, 2009
- Glaciers help actively growing mountains become higher - Sep 16, 2010
- Melting glaciers to contribute 12cm to world sea-level increases by 2100 - Jan 11, 2011
- 50mn-yr-old mountains did not evolve from Tibet-like plateau: Study - Dec 18, 2010
- Wind 'can be 10 to 100 times more effective in eroding mountains' - Mar 29, 2011
- Glaciers melting 100 times faster - Apr 04, 2011
- Glacial erosion changes internal mountain structure, responses to plate tectonics - Nov 18, 2008
- Scientists estimate sea level rise by studying past carbon dioxide levels - May 02, 2011
- Venice will sink three inches by 2032 - Mar 21, 2012
- Glaciers 'melting 100 times faster than at any time in 350 yrs' - Apr 04, 2011
- Antarctica was once a tropical paradise - Aug 02, 2012
- Organic polymer protects burnt forest soil - Dec 23, 2011
- World's oldest meteor impact crater discovered - Jul 01, 2012
Tags: beryllium, climatic cycles, climatic variations, cosmic radiation, european mountains, geodesy, geosciences, geoscientists, german research centre, glacial period, himalayas, isotopes, land surface, millimetre, mountain erosion, precise methods, rare isotope, swiss alps rivers, two continents, wittmann