Scientists from the University of Kansas, USA, believe that the Earth is a kind of pulse - approximately every 60 million. years of the continents rise, then fall to its original place.
What is a tectonic mechanism makes the earth throb as it is not clear, but it is likely these rises due to the mysterious mass extinction of marine life, has been at least 500 million. years, though occurring on schedule with this periodicity. During the boom of the continents of the sea are too small length of many species that do not allow them to survive, writes. CNews.
The scientists made their conclusions based on chemical analysis of marine resources. Whenever there was a mass extinction, every once in its victims revealed the high content of strontium -87. According to Professor of Physics and Astronomy Melotta Adrian, who heads the Kansas study, this isotope is obtained for the decay of another element, rubidium contained in the continental crust and is selected out during powerful eruptions of lava. When there are continental rises, he says, the sea gets a lot of strontium -87, increasing its concentration in water in relation to its other isotope - strontium -86.
He gets there in the form of rubidium from the continental crust, which is poured onto the surface with lava, and then transformed into an isotope of strontium. He gets there and in the form of strontium isotope contained in the rocks, because during the boom they are exposed to strong erosion - landscapes at this point are mountainous, the waters flowing from the mountains quickly, the soil washed away from them and eventually taking it into the sea.
Prof. Melott believes the earth pulsations most acceptable, if not the only explanation for the periodic mass extinctions of marine life. Causes of the world's pulse, as has been said, is not completely clear, but some scientists believe it has something to do with the rise of the lava ...
While the theory of Melotta applies only to the Americas. The professor believes that the same should happen with other continents, but this requires further study.
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