| Supai Group | |
|---|---|
| Stratigraphic range: Pennsylvanian–Lower Permian, | |
 Example Supai red beds, north projecting ridgeline, South Rim, Grand Canyon | |
| Type | Geologic group |
| Sub-units | 4 named subunits: 4-Esplanade Sandstone 3-Wescogame Formation 2-Manakacha Formation 1-Watahomigi Formation |
| Underlies | Hermit Formation |
| Overlies | Redwall Limestone, Surprise Canyon Formation and Naco Formation[1][2]: 129 |
| Thickness | 1,000 feet (300 m) approximate maximum[2]: xviii |
| Lithology | |
| Primary | sandstone, siltstone, mudstone |
| Location | |
| Coordinates | 36°13′27″N 112°41′38″W / 36.22417°N 112.69389°W |
| Region | Colorado Plateau |
| Country | United States |
| Extent | Virgin River valley, Grand Canyon, Sycamore Canyon and Verde Valley |
| Type section | |
| Named for | Supai, Arizona |
| Named by | N.H. Darton |
| Year defined | 1910 |
  Supai Group (the United States)  Supai Group (Arizona) | |
The Supai Group is a slope-forming section of red bed deposits found in the Colorado Plateau. The group was laid down during the Pennsylvanian to Lower Permian. Cliff-forming interbeds of sandstone are noticeable throughout the group. The Supai Group is especially exposed throughout the Grand Canyon in northwest Arizona, as well as local regions of southwest Utah, such as the Virgin River valley region. It occurs in Arizona at Chino Point, Sycamore Canyon, and famously at Sedona as parts of Oak Creek Canyon. In the Sedona region, it is overlain by the Hermit Formation, and the colorful Schnebly Hill Formation.
The Supai Group is coeval with the Hermosa Group of east and south Utah; the Hermosa Group extended southeastwards from Utah to Durango,[2]: 54 extreme southwest Colorado, and adjacent to the Hermosa type section.
The Supai Group was originally designated as the Supai Formation by N.H. Darton in 1910 for exposures at Supai, Arizona.[3] It was first raised to group stratigraphic rank by E.H. McKee in 1975,[4] though it remains at formation rank at other locations where its subunits are difficult to distinguish.[5]
- ^ Huntoon, PW; et al. (1995). Geologic map of the eastern part of the Grand Canyon National Park, Arizona (Map). Grand Canyon Association.
- ^ a b c Blakey, Ron; Ranney, Wayne (2008). Ancient Landscapes of the Colorado Plateau. Grand Canyon Association. ISBN 9781934656037.
- ^ Darton, N. H. (1910). "A reconnaissance of parts of northwestern New Mexico and northern Arizona". U.S. Geological Survey Bulletin. 435. doi:10.3133/b435. hdl:2346/65058.
- ^ McKee, E.D. (1975). "The Supai Group; subdivision and nomenclature". U.S. Geological Survey Bulletin. 1395-J. doi:10.3133/b1395J.
- ^ Blakey, Ronald C. (1 September 1990). "Stratigraphy and geologic history of Pennsylvanian and Permian rocks, Mogollon Rim region, central Arizona and vicinity". GSA Bulletin. 102 (9): 1189–1217. doi:10.1130/0016-7606(1990)102<1189:SAGHOP>2.3.CO;2.