Toroweap Formation

Toroweap Formation
Stratigraphic range:
late early Permian,
Toroweap Formation in Grand Canyon National Park
TypeGeological formation
Sub-unitsSeligman, Brady Canyon, and Woods Ranch members (oldest to youngest)
UnderliesKaibab Limestone
OverliesCoconino Sandstone
Thickness200 feet (61 m) approximate maximum.
Lithology
Primaryred beds, gypsum, and fossiliferous limestone
Otherdolomite
Location
Coordinates36°12′19.34″N 113°05′24.40″W / 36.2053722°N 113.0901111°W / 36.2053722; -113.0901111
Region(southwest)-Colorado Plateau
Northern Arizona, southeast Utah
ExtentGrand Canyon, North Rim, (Kaibab Plateau), also South Rim, and elsewhere in Arizona, Utah, Nevada
Type section
Named forToroweap Valley, Arizona
Named byMcKee (1938)

The Toroweap Formation outcrops as a distinct layer of generally darker, interbedded slope- and cliff-forming strata lying between the brighter colored cliffs of the Kaibab Limestone above, and Coconino Sandstone below. It outcrops in Grand Canyon, Arizona, Southwestern United States, found throughout walls of the South Rim, Grand Canyon, and the North Rim, of the Kaibab Plateau. Also, it outcrops in the Kaibab's southeast extension to Cape Royal, the Walhalla Platea. The formation is also found in southeast Utah and west-central Nevada.