This zoomed-in view shows the inner gorge of the Grand Canyon in the Phantom Ranch area. The trail across the Tonto Platform to the Plateau Point overlook is in the lower left. A nonconformity between the Precambrian-age metamorphic rock and red, layered, sedimentary rocks (also of the Precambrian-age) is visible across the inner gorge from the overlook. Another unconformity (an angular unconformity) separates the Precambrian-age sediments from the massive Tapeats Sandstone (of Cambrian age); this feature is known as the Great Unconformity and is an observable stratigraphic boundary beneath Cambrian-age sedimentary rocks throughout much of North America. The Tapeats is overlain by the softer, slope-forming Bright Angel Shale that forms the gray, barren slopes of the Tonto Platform above the inner gorge. Bright Angel Canyon is in the upper right. Phantom Ranch, located at the confluence of Bright Angel Creek with the Colorado River, is to right of the center of this image. This view is from Rim Trail at Canyon Village. |