Supai Group

Supai Group Stratigraphic range: Pennsylvanian—Lower Permian, 318–287 Ma PreЄ Є O S D C P T J K Pg N
Example Supai red beds, north projecting ridgeline, South Rim, Grand Canyon
Type	Geologic group
Sub-units	4 named subunits, Esplanade Sandstone, Wescogame Formation, Manakacha Formation, Watahomigi Formation
Underlies	Hermit Formation-(Permian), Grand Canyon; (Hermit elsewhere in Arizona, (west) Oak Creek Canyon region, Sedona, AZ (townsite))
Overlies	Redwall Limestone; locally in Grand Canyon,Surprise Canyon Formation Naco Formation, south and southeast Mogollon Rim region, central Arizona
Thickness	1,000 feet (300 m) approximate maximum
Lithology
Primary	sandstone, siltstone, mudstone
Location
Region	(southwest)-Colorado Plateau Northern Arizona, Grand Canyon; basement rocks of Verde Valley, Mogollon Rim, etc. AZ; also, southwest Utah
Extent	Extreme southwest Utah (Virgin River valley region; in Arizona: Grand Canyon, Sycamore Canyon, Verde Valley, and buried units at south of Colorado Plateau

The Pennsylvanian to Lower Permian, (end of the Paleozoic Era), Supai Group, is a slope-forming section of red bed deposits found at the southwest-to-south Colorado Plateau. Cliff-forming interbeds (sandstone) are noticeable throughout the group, as well as the largest cliff-former the topmest member Esplanade Sandstone. The Supai Group is especially exposed throughout the Grand Canyon in northwest Arizona, as well as local regions of southwest Utah (Virgin River valley region). It outcrops southeastwards in Arizona at Chino Point (south Aubrey Valley), 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, extreme southwest Colorado, and adjacent to the Hermosa type section.

The oldest member (Early Pennsylvanian), the Watahomigi Formation is from sedimentary basins. It is composed of red mudstone, sandstone, and tan limestone. As ocean levels rose, basins filled, and the Manachka Formation was laid down (especially in the Grand Canyon). Continentally aeolian sand became more widespread; the coeval Weber Sandstone was deposited in northeast Utah (Dinosaur National Monument region, northeast of the Uncompahgre Uplift).