The Farallon plate became less steep

Now, it's 85 million years ago.The Farallon Plate becomes less steep,causing volcanism to stretch eastward and eventually cease. As the Farallon Plate subducts,it compresses North America,thrusting up mountain ranges like the Rockies, which extend over 3,000 miles.Soon after, the Eurasian Plate rifts from North America,opening the North Atlantic Ocean.We'll fast forward again.The Colorado Plateau now uplifts,likely due to a combination of upward mantle flow and a thickened North American Plate.