Second super-fast flip of Earth's poles found
Updated 12:04 03 September 2010
On the flip, in record time (Image: G.Glatzmaier/Los Alamos National Laboratory/P.Roberts/UCLA/SPL)在翻轉，以創記錄的時間
SOME 16 million years ago, north became south in a matter of years. Such fast flips are impossible, according to models of the Earth's core, but this is now the second time that evidence has been found.
約 一千六百萬年前，北方在幾年時間成為南方。這種快速翻轉是不可能的，根據地心的模型，但現在這是第二次證據被發現。
The magnetic poles swap every 300,000 years, a process that normally takes up to 5000 years. In 1995 an ancient lava flow with an unusual magnetic pattern was discovered in Oregon. It suggested that the field at the time was moving by 6 degrees a day - at least 10,000 times faster than usual. "Not many people believed it," says Scott Bogue of Occidental College in Los Angeles.
磁極每隔30萬年互換，一過程一般需要長達 5,000年。 在1995年一古老的熔岩流與一極不尋常的磁性模式在俄勒岡州被發現。它提出在那時的場是以每天6度移動的， - 至少10,000倍於平常速度。 “不是很多人相信它，”洛杉磯西方學院的斯科特博格說。
Now Bogue and his colleague Jonathan Glen of the United States Geological Survey in Menlo Park, California, say they have found a second example in Nevada. The lava rock suggests that in one year, Earth's magnetic field shifted by 53 degrees (Geophysical Research Letters, DOI: 10.1029/2010GL044286). At that rate, a full flip would take less than four years, but there could be another interpretation. "It may have been a burst of rapid acceleration that punctuated the steady movement of the field," says Bogue.
現在博格和他的同事在加州Menlo 公園美國地質調查局的喬納森格倫，說他們已經在內華達州找到第二個例子。熔岩岩石表明在某一年，地球的磁場滑移53度（地球物理研究快報，個人主頁：10.1029/2010GL044286）。按照那速度，一次全完翻轉將需不超過 4年，但有可能是另一種解釋， “它可能已是一次急劇加速的爆炸，它不時打斷穩定的場移動，”博格說。
Peter Olson of Johns Hopkins University in Baltimore, Maryland, remains sceptical and points out that the effects could have been local rather than global.
在馬里蘭波爾的摩約翰霍普金斯大學的，仍抱懷疑態度和指出，影響可能已是局部地區性而非全球性的。
Earth is overdue for a reversal, and rapid shifts would cause widespread chaos - for navigation and migratory birds for instance.
地球是逾期作一逆轉，急速的滑移將會引起廣泛的混亂 - 對於導航和候鳥作實例。
http://www.newscientist.com/article/mg20727765.000-second-superfast-flip-of-earths-poles-found.html
解釋這 - 太陽會急速轉軸360度
龐大的媒體封鎖關於地球和月球的軌道改變？
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