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Revising its course

  • 29/11/2006

The world's largest drainage system, the Amazon river, has gone through three different stages of drainage since the mid-Cretaceous period, says a team of geologists from the US and Brazil. In the beginning, the Amazon was flowing as it does now: from the Andes Mountains of Peru to the Atlantic Ocean. Its first change of course occurred 130 million years ago due to the break-up of the South American and African continents. The east coast of South America was raised and the river flowed from the Atlantic to the Pacific Ocean. Later, the Andes started growing and the Amazon's current again took a west-to-east course.

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