As the Earth is estimated at about 4.6 billion years, the researchers now say that perhaps that part of the original crust of our planet are still in place today. Scientists find evidence of isotopic 2.7 trillion years ' parental ' Stone Shield samples Canada, suggested the oldest crust Congratulations formation features of this continent.
In a new study, researchers from the University of Ottawa and the Carnegie Science analyzes the ratio of isotopes of samarium and neodymium stone Superior Province, which is located in the northern part of the Great Lakes. This sample is mainly composed of granite which 2.7 billion years old, formed by rocks, rich in magnesium recycling. "This area of Northern Quebec is the core of the shield of Canada," explains Jonathan O'Neil Professor, Department of Earth and environmental sciences at the University. ' Previous work has shown that if we have a sense of something more, of this ancestor, it'll be there. ' First the crust has been driven primarily through inner geological activity, it is difficult to identify the nature of. However, with certain isotopes, the researchers were able to study Earth's early ' time '. This, in turn, revealed the signing rock. Samarium-146 has a half-life of just 103 million years, which runs on a geological time scale. And, while it existed at the time of the formation of the Earth, become extinct from the beginning.
The researchers determined that the sample contained revised skin from more than 4.2 billion years ago. We can now better understand how the core of the continent at that time table, "said O'Neil. There is a complex history of cortical recycling and return to combine, by the stone that always constantly recycled and returned to melt that way-and delete a lot of information about his early life, or when it comes '. ' If this means that the tectonic plates are not working during the first part of the Earth's history can now be investigated by using our tool variations of neodymium-142 a study to track the role of crust really old buildings are old, but still young, part of the continental crust of the Earth, ' said Richard Carlson of the Carnegie. According to o ' Neil, the result of allowing scientists to better determine the age of the bedrock. ' Has become a 4.2 billion years older, almost as old as 4.3 billion years, said O'Neil. ' Therefore, we can piece the puzzle together to try to understand how the first continents formed and the core of our oldest continent '.
THE CRUST IS NOT
Geoscientists from the University of Chicago calculated the mass before and after the India-Asia collision system, consider the many ways in which you can distribute. This process is very slow, causing 60 million years and continues today. New calculations reveal the enormous difference in mass. After the collision, the refugees have only behaved in some ways, explained tim.
Some are forced upward, creating the Himalayas, while some are eroded and deposited as sedimentary deposits in the great sea. And some squeezed out the sides, forming the Southeast Asia.
This, however, still leaves most of the existence of which is not known, and scientists say that this could be explained only if the parcel is lost deep in the mantle.
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