We thought global ice erased a billion years of history but new evidence points to ancient supercontinents.
Credit: PBS/NOVA.
When geologist John Wesley Powell explored the Grand Canyon in 1869, he noticed a glaring omission in the rocks. A layer of rock just 520 million years old sat directly on top of a… [+7330 chars]
Discussion (0)
No comments yet. Be the first to share your thoughts!
Join the Conversation
You need to be logged in to leave a comment.
Sign In Create Account