Continental Crust Emerged 500 Million Years Earlier Than Previously Thought

Earth's continental crust forming.

The first emergence and persistence of continental crust on Earth during the Archaean Eon (4 billion to 2.5 billion years ago) has important implications for plate tectonics, ocean chemistry, and biological evolution, and it happened about half a billion years earlier than previously thought. (Image: Simone Marchi via SwRI)