The layers you see in this image were once iron-rich and silica-rich sediments that settled on an ancient sea floor 2.7–2.4 billion years ago. Credit: The Australian Museum The layers you see in this ...

Rivers may have operated on a global scale around 3.5 billion years ago. The new find comes courtesy of ancient rocks in China and South Africa. A change in rock chemistry around that time provides ...

Rocks in West Greenland resemble cake marbled with chocolate and vanilla. They’re now the oldest evidence of Earth’s magnetic field. Isua Supracrustal Belt rocks contain an alternating banded iron ...

This photo shows an example of the 3.7 billion year-old banded iron formation found in the northeastern part of the Isua Supracrustal Belt. Geologists at MIT and Oxford University have uncovered ...

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