Sydney. (EFE). – The core Earth rotate at different speeds, often accelerating and decelerating, and this movement is not synchronized with the rest mass of the planet, according to a study released today in Australia.
The research led by Hrvoje Tkalcic Australian National University (ANU) revealed that not only the turnover of the core is different from the mantle , the layer which is below the crust, but also its speed is variable.
“is the first experimental evidence that the core rotates at different speeds,” he said in a news Tkalcic ANU.
The researchers found that compared with the mantle, the core rotating faster in the 1970s and 1990s, but slowed in the 80s.
“The dramatic acceleration probably occurred in recent years, but need to do more tests to confirm this observation,” said Tkalcic, recalling that Edmund Halley speculated that the inner layers of the Earth rotating at different speeds in 1692.
For purposes of the study, one skilled in physics and mathematics analyzed, through a novel method of earthquakes records doublets the past 50 years for measuring the speed of rotation of the earth’s core.
earthquake doublets are two almost identical magnitude earthquakes that can be registered in a period ranging from a few weeks to 40 years, and which differ from the replicas.
Tkalcic
commented that it seemed exciting to see that “even with a difference of ten, twenty or thirty years, these earthquakes are similar. Each pair has a slight difference, and this corresponds to the core.’ve been able to use that difference to rebuild the story of how the core has rotated in the last fifty years. “
Tkalcic think your new method will help the understanding of the Earth’s core role in the creation of the magnetic field that allowed the evolution of life on the planet to act as a shield against cosmic radiation, the statement of the ANU.
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