The Cutler Formation is composed of thick, arkosic, alluvial sandstones shed southwestward from the Uncompahgre highlands into the Paradox Basin. Salt tectonism played an important role in deposition of the Cutler in some areas. In the northeast part of the basin, more than 8,000 ft, and as much as 15,000 ft, of arkose was trapped between rising salt anticlines - this arkose is thin to absent over the crests of some anticlines. In the western and southern parts of the basin, the Cutler is recognized as a Group consisting of, in ascending order: the lower Cutler beds, Cedar Mesa Sandstone, Organ Rock Formation, White Rim Sandstone, and De Chelly Sandstone. The aggregate thickness of these formations is less than 2,000 ft. The formations of the Cutler Group were deposited in a complex system of alluvial, eolian, and marine environments characterized by abrupt vertical and lateral lithologic changes. The basal Cutler is Pennsylvanian in age, but the bulk of the Group was deposited during the Permian. The Cutler is conformably underlain by the Pennsylvanian Hermosa Group across most of the basin. It is overlain unconformably by the Permian Kaibab Limestone in the western part of the Paradox Basin. The Cutler or Kaibab are overlain unconformably by the Triassic Moenkopi or Chinle Formations.