When most of us think about the impressive geology of the Grand Canyon, our focus is on the ancient rocks. Within the past 1 million years, however, volcanoes have created striking displays in the canyon. Hot lava often flowed down the Colorado River channel for tens of miles; other times, it dammed the river, impounding water behind dams that eventually breached, sometimes releasing catastrophic floods.
Towering cliffs, plateaus, arches, and narrow canyons are iconic symbols of southern Utah’s Red Rock Country. Another type of landform captured my attention during recent explorations: mile after mile of gently rolling rock-covered terrain, giving the impression of being surrounded by an ocean of sandstone. An arid sand sea of shifting dunes created these rocks many millions of years ago.