During the Pennsylvanian and the Permian, the final assembly of the Appalachian Mountains to the elevation of the Himalayas occurred with the Alleghanian orogeny and the formation of the supercontinent Pangaea. Glaciation of the southern hemisphere raised and lowered sea levels in Arizona, creating the ledge and slope topography common in the Grand Canyon, Sedona and Monument Valley, with alternating layers of siltstone, limestone, sandstone, dolomite and shale. The Kaibab Limestone is a famous formation from this time, covering much of northern Arizona.