HOW WAS OUR REGION FORMED?
In ancient times, oceans and then deserts covered western Colorado. Their retreat left great deposits including sand, which compressed into sandstone. To the west of Grand Junction, the red sandstone has weathered into the canyons and elaborate formations of the Colorado National Monument. East of the Grand Valley is the vast, flat-topped Grand Mesa. Volcanic flows had covered that area, forming a protective layer of hard basalt, hundreds of feet deep. The surrounding terrain eroded away, leaving the Grand Mesa with its 10,000′ elevation, forests, and lakes.
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