The Grand Canyon of the Yellowstone is the first large canyon on the Yellowstone River downstream from Yellowstone Falls in Yellowstone National Park in Wyoming. Past and current hydrothermal activity altered and weakened the rhyolite, making the rocks softer. The Yellowstone River eroded these weakened rocks to deepen and widen the canyon, a process that continues today. The multi-hued rocks of the canyon result from the hydrothermally altered rhyolite and sediments. Look closely at dark orange, brown, and green areas near the river for still-active hydrothermal features. Their activity—and that of water, wind, and earthquakes—continue to sculpt the canyon.
Loading contexts...
