Loading AI tools
Geologic formation in the Grand Canyon From Wikipedia, the free encyclopedia
The Permian Hermit Formation, also known as the Hermit Shale, is a nonresistant unit that is composed of slope-forming reddish brown siltstone, mudstone, and very fine-grained sandstone. Within the Grand Canyon region, the upper part of the Hermit Formation contains red and white, massive, calcareous sandstone and siltstone beds that exhibit low-angle cross-bedding. Beds of dark red crumbly siltstone fill shallow paleochannels that are quite common in this formation. The siltstone beds often contain poorly preserved plant fossils. The Hermit Formation varies in thickness from about 100 feet (30 m) in the eastern part of the Grand Canyon region to about 900 feet (270 m) in the region of Toroweap and Shivwits Plateaus. In the Sedona, Arizona area, it averages 300 feet (91 m) in thickness. The upper contact of the Hermit Formation is typically sharp and lacks gradation of any kind. The lower contact is a disconformity characterized by a significant amount of erosional relief, including paleovalleys as much as 60 feet (18 m) deep.[1]
Hermit Formation | |
---|---|
Stratigraphic range: Permian, Early Leonardian[1][2] | |
Type | Geological formation |
Underlies | Coconino Sandstone |
Overlies | Supai Group |
Thickness | 900 feet (270 m), at maximum |
Lithology | |
Primary | siltstone and mudstone |
Other | sandstone |
Location | |
Region | Arizona-(North & Central Arizona) California-(southeast) and Utah-(southern) |
Country | United States-(Southwestern United States) |
Type section | |
Named for | Hermit basin, Coconino County, Arizona[3] |
Named by | Noble (1923)[3] |
Seamless Wikipedia browsing. On steroids.
Every time you click a link to Wikipedia, Wiktionary or Wikiquote in your browser's search results, it will show the modern Wikiwand interface.
Wikiwand extension is a five stars, simple, with minimum permission required to keep your browsing private, safe and transparent.