Lower part is Virgin River gorge, upper part, is a striking desert landscape of cross-bedded sandstone. This is characteristic of a cut in strong rock. Canyon erodes by breaking of rock at joints. During the process, stream erosion undercuts a wall, then a block falls off at a joint.
Joints are vertical, so walls are vertical.
Cedar Breaks is further north, along the west edge of the Colorado Plateau. Alternating narrow, North-South trending ranges, separated by flat basins. Contines all the way to edge of the Sierra Nevada Mountains. Thus, the edge of the Plateau is a large fault. Varying amounts of oxidized iron cause the units to develop a range of red, pink, and creme color.