Organ Rock Formation Organ Rock Formation The Organ Rock Formation or Organ Rock Shale is a formation within the late Pennsylvanian to early Permian Cutler Group and is deposited across southeastern Utah, northwestern New Mexico, and northeastern Arizona. This formation notably outcrops around Canyonlands National Park, Natural Bridges National Monument, and Monument Valley. The age of the Organ Rock is constrained to the latter half of the Cisuralian Epoch by age dates from overlying and underlying formations. Important early terrestrial vertebrate fossils have been recovered from this formation in northern Arizona, southern Utah, and northern New Mexico. These include the iconic Permian terrestrial
Vermilion Cliffs by settlers during the 19th Century. The area was explored by the Mormon pioneer and missionary Jacob Hamblin, who started a ranch at the base of the cliffs in House Rock Valley. Present day U.S. Highway 89A basically follows the old wagon route past the cliffs through House Rock Valley and up the Kaibab Plateau to Jacob Lake. Famous locations in the cliff area include Lee's Ferry, Glen Canyon and the Glen Canyon National Recreational Area, The Wave, Coyote Buttes, and others. Reddish or vermilion-colored cliffs are found along U.S. Highway 89A near Navajo Bridge, and may be seen from