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英语翻译
Groundbreaking research by two French geophysicists to shed some light on the mystery.Using 80 metres of deep sea sediment core,they have obtained measurements of magnetic-field intensity that span 11 polarity reversals and four million years.The analysis reveals that intensity appears to fluctuate with a clear,well-defined rhythm.Although the strength of the magnetic field varies irregularly during the short terra,there seems to be an inevitable long-term decline preceding each polarity reversal.When the poles flip-a process that takes several hundred thousand years-the magnetic field rapidly regains its strength and the cycle is repeated.
Groundbreaking research by two French geophysicists to shed some light on the mystery.Using 80 metres of deep sea sediment core,they have obtained measurements of magnetic-field intensity that span 11 polarity reversals and four million years.The analysis reveals that intensity appears to fluctuate with a clear,well-defined rhythm.Although the strength of the magnetic field varies irregularly during the short terra,there seems to be an inevitable long-term decline preceding each polarity reversal.When the poles flip-a process that takes several hundred thousand years-the magnetic field rapidly regains its strength and the cycle is repeated.
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