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Monday, November 23, 2009

Photo: Global Cooling Chilled Super-Hot Oceans of Early Earth, Study Finds


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A cross-section of a chert sample from China, dated at 1.4 billion years old, shows the structures of silica at a microscopic scale.

A new study of the silicon found in chert determined that a period of global cooling chilled the oceans of ancient Earth from temperatures as high as 158 degrees Fahrenheit (70 degrees Celsius) 3.5 billion years ago to 68 degrees Fahrenheit (20 degrees Celsius) about 600 million years ago.

Image courtesy Marc Chaussidon/Nature