Today, Lees Ferry is the starting point for raft trips through the Grand Canyon. This view is looking downstream toward the mouth of Marble Canyon. Rock formations in the Lees Ferry area include the Kaibab Limestone, Moenkopi Formation, Chinle Formation, and undivided Glen Canyon Group. The top of the Kaibab Limestone is visible near water level near the center of the image. The red -brown, shaley slope and cliff on the left is the Moenkopi Formation. The cliffs in the Moenkopi Formation are called the "Chocolate Cliffs." The Chocolate Cliffs are the low escarpment in the canyon (in the middle-right side of this image). The shales of the Chinle Formation are responsible for the broad flats and slopes above the Chocolate Cliffs. The higher, more distant, Vermilion Cliffs are associated with the red sandstones of the Glen Canyon Group. Near the center of this image, terraces of alluvial gravels of Quaternary age are exposed along the canyon below the "Chocolate Cliffs" escarpment of the Moenkopi Formation.