Megaflood 'made Island Britain'
By Jonathan Amos
Science reporter, BBC News
The megaflood made Britain what it is today, geographically
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Britain became separated from mainland Europe after a catastrophic flood some time before 200,000 years ago, a sonar study of the English Channel confirms.
The images reveal deep scars on the Channel bed that must have been cut by a sudden, massive discharge of water.
Scientists tell the journal Nature that the torrent probably came from a giant lake in what is now the North Sea.