Bass limestone 1.19 billion years old. Trail of Time exhibit, South Rim, Grand Canyon National Park, Arizona, USA.
Bands of pink and white layers demark the 1.19-billion-year-old Bass limestone of the Grand Canyon Supergroup, on the fascinating Trail of Time interpretive exhibit on the South Rim of Grand Canyon National Park, Arizona, USA. Starting west of Yavapai Geology Museum, walk for 1.3 miles on the paved trail backward in time from today toward the oldest rock in Grand Canyon, Elves Chasm gneiss, 1.840 billion years old. Or begin east of Verkamp's Visitor Center, walking forward in time toward the youngest rock in the Grand Canyon, Kaibab Limestone, 270 million years old. Starting at least 5 to 17 million years ago, erosion by the Colorado River has exposed a column of distinctive rock layers, which date back nearly two billion years at the base of Grand Canyon. While the Colorado Plateau was uplifted by tectonic forces, the Colorado River and tributaries carved Grand Canyon 6000 feet deep, 277 miles long and up to 18 miles wide.Add to Cart Add to Lightbox Download