If the earth tilts a bit more in spinning

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   Another Intresting news.....

Earth might have spun on its side to keep its balance in the distant past, and could do so again, scientists reported today. Alaska was suddenly at the equator, the thinking goes. Scientists already know that the North Pole wanders over time. 

But a theory known as true polar wander suggests that if a very heavy object, like an oversized volcano forms far from the equator, the force of the planet's rotation would pull the object away from the axis the Earth spins around. 

Should a mass such as the very heavy volcano become unbalanced, Earth would tilt and rotate itself until the extra weight moves somewhere near the equator. Analysed samples of ancient sediments found in the Norwegian archipelago of Svalbard show that such an event may have indeed happened in the past. 

"The sediments we have recovered from Norway offer the first good evidence that a true polar wander event happened about 800 million years ago," said Adam Maloof, professor of geosciences at Princeton University. 

THE EVIDENCE 

When rock particles sink to the ocean floor, small magnetic grains within the particle align with the magnetic lines of the Earth. These rocks then become records of the Earth's magnetic field at the time that they were pointing. If a rock has been spun by an unusual geological event, the orientation of its magnetic field will be out of the ordinary. "We found just such anomalies in the sediments," Maloof said. "We made effort to find another reason, such as a rapid rotation of the crustal plate the islands rest upon, but none of them makes as much sense as a true polar wander event when taken in the context of geochemical and sea level data from the same rocks." 

FLOWING BACKWARDS 

The polar wander could also be responsible for the unusual changes that happened in ocean chemistry 800 million years ago. "Scientists have found no evidence for an ice age occurring 800 million years ago, and the change in the ocean at this juncture remains one of the great mysteries in the ancient history of our planet," Maloof said. 

"But if all the continents were suddenly flipped around and their rivers began carrying water and nutrients into the tropics instead of the Arctic, it could produce the mysterious geochemical changes science has been trying to explain." 

Future work can test the true polar wander hypothesis as this type of event would affect every continent in a predictable manner, depending on the continent's changing position relative to Earth's spin axis. 