Africa breaks in two to make way for a new ocean.
A couple of years ago a huge crack opened in the middle of a road in Kenya. The continent seems to be splitting in the open, although scientists know this has been going on for 20 million years. New research in Nature now offers GPS data on how the process is, one of the most primitive of the formation of continents.
Like a race on an average, a huge crevasse of several kilometres left the Kenyans speechless, covering the route between Nairobi and Narok a couple of years ago. In the eyes of the eyes, the African continent separates and what is now land will become a new ocean. Somalia, Kenya and Ethiopia will drift away in a few million years. This geological scar appeared on the ground surprised half the world. Specifically to that environment formed by the laymen in geology who understood, we understood, in a palpable way that the Earth is dynamic and is in constant evolution. However, for those who are dedicated to studying tectonic plates is not so spectacular because they know that this separation began about 20 million years ago. The whole East Africa is moving away from the rest of the continent, making this place an interesting point at a geological level, because here «you can appreciate the most primitive stage of the formation of the continents», says Francisco Manuel Alonso Chaves, researcher in the Area of Internal Geodynamics at the University of Huelva.
Now, a study by the University of Potsdam, published in Nature, comes to confirm with GPS data how the formation of the new ocean and the displacement movements in the area are taking place. The East African Rift Valley extends some 3,000 km from the Gulf of Aden in the north to Zimbabwe in the south, dividing the African plate into two unequal parts: the Somali and Nubian plates. This Rift is peculiar in its size. The Earth is always in tension because it is formed by plates. These separate at one point, but somewhere else they have to come together. However, all of these processes do not occur on a human scale. Even if we see a crack, the processes happen far below», says Manuel Regueiro, president of the Distinguished College of Geologists (ICOG).
The planet as we know it now began to gestate 13 billion years ago. The continents did not exist until about 3.5 billion years ago (when Pangaea broke). Examples of this evolution of the Earth are also found in the Iberian Peninsula. Hundreds of years ago Galicia was where the American Appalachians now stand. When this whole block collided with the Eurasian plate the Pyrenees were formed. With the current dynamic, 250 million years from now, Spain will be at the North Pole», continues the president of ICOG.
Returning to Africa, the remnants of Earth’s movements are everywhere... The shape of the island of Madagascar seen on a map gives us a clue to what is happening in the subsoil, since hundreds of years ago it separated from the rest of the continent.
It is not so obvious that India precisely left here and was, long before man on Earth, stuck to this part of the world. About 70 million years ago. Once separated, it began its drifting sea migration towards the Eurasian plate. Once he found it, the collision formed the Himalayan mountains. An elevation of the terrain indicating that one plate overlapped over the other more than 1,000 km. The evolution of the planet over hundreds of years can be seen through a map of the world. If you want to look for an example of one of the most advanced stages of the formation of the present continents, you can look at the Atlantic ridge. The original fracture that ended up forming South America and Africa is perfectly appreciated there. An intermediate stage would be, for example, the Red Sea, where about 10-20 million years ago the Arabian Peninsula conformed to the black continent. The Indian Ocean penetrated here», says Alonso Chaves.
MATHEMATICAL MODEL
One of the keys to this recent article in Nature lies in the fact of confirming with accurate data, collected through satellites (GPS) and not with ground measurements, what the science and theory of plate tectonics has already known for decades. Of course, this theory of plates was imposed as a fundamental paradigm recently, in the 1970s. «This allows us to make a mathematical model and study the displacement over the years», Alonso continues.
Another interesting detail from the recent article is that the Victoria microplate, which surrounds the area of the Great Lakes, moves counter-clockwise, the reverse of how the neighbors do it, for example the plate that includes Somalia. The East African Rift System is a plate tectonic boundary that includes several smaller arms or plates. The graphs published by the researchers show that this microplate is separated by the South, by Kenya, while above the movement is smaller. The region of the lakes is all along the divide that will divide the continent. This rotation explains the geological history of a unique area, which besides large lakes, also includes mountains»
You Might Also Like :
0 commenti:
Post a Comment