In 1869, John Wesley Powell was studying layers of rock in the Grand Canyon when he noticed an unconformity in the layers. Around a billion years were missing, and the problem turned out to be global.
James is a published author with multiple pop-history and science books to his name. He specializes in history, space, strange science, and anything out of the ordinary.View full profile James is a ...
Las Vegas locals began a project in the 1990s to protect a geological marvel at the edge of town. They made educational signs and were joined by politicians including late Sen. Harry Reid and ...
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