Is Arizona's most beautiful place an iconic red rock butte, a blue-green waterfall or an otherworldly cave formation? Vote in our stunning views poll.

The origins of plate tectonics on Earth are hotly debated, but evidence from Australia now shows that parts of the crust ...

On Wednesday, Sotheby’s will auction off a chunk of rock believed to have originated on Mars for an anticipated two to four ...

Geology is full of detective stories about the Earth's history, and a new paper in Geology by University of New Mexico ...