Zion National Park's Dinosaur-Shaking Earthquakes

Long ago, when Earth had one continent and one ocean, an earthquake rippled through western North America's sea of sand. The early Jurassic earthquake left its mark in the vast dunes that now form the red cliffs of Zion National Park in Utah.



via LiveScience.com http://www.livescience.com/39117-navajo-sandstone-dunes-jurassic-earthquake.html