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.

NFL draft kicks off Thursday night in Green Bay. We'll have full Round 1 coverage of who is picked and how it impacts the ...

Scientists found that a "cap" of bubbles and magma stands between the magma reservoir underneath Yellowstone National Park ...