A weathered sign in the Minnesota River Valley proudly proclaims: “World’s Oldest Rock.” Erected in 1975, it marks a 3.8-billion-year-old gneiss — or so scientists thought.

Rather than a volcanic winter, the Toba eruption 74,000 years ago resulted in several years of warm and dry weather, ...

How core-mantle differentiation influenced the distribution of volatile elements on Earth. Imagine Earth's history as a ...

Watch the Earth's tectonic plates grow, shrink, and jostle for position in this new model of the last billion years on the ...