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→‎Structure: "Structure" has an entirely different meaning in geology than what is described below. Either "contacts" or "boundaries" should be used. "Contacts" is preferred usage - see AGI's Glossary of Geology."
→‎Features: As used in the sidebar "Lithology" is the proper terminology.
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'''Redwall Limestone''' is a resistant [[cliff-former|cliff-forming]] unit that forms prominent, red-stained cliffs that range in height from {{convert|500|ft|m|sp=us}} to {{convert|800|ft|m|sp=us}}, and date to the [[Mississippian age]].
'''Redwall Limestone''' is a resistant [[cliff-former|cliff-forming]] unit that forms prominent, red-stained cliffs that range in height from {{convert|500|ft|m|sp=us}} to {{convert|800|ft|m|sp=us}}, and date to the [[Mississippian age]].


==Features==
==Lithology==
Redwall Limestone consists predominately of light-olive-gray to light-gray, thin-bedded, fine- to coarse-grained, thin- to thick-bedded, often cherty, [[limestone]]. Its lower part consists of brownish-gray, interbedded finely crystalline [[dolomite]] and fine- to coarse-grained limestone with layers of white [[chert]] lenses and yellowish-gray and brownish-gray, cliff-forming, thick-bedded, fine-grained dolomite. It is divided into Horseshoe Mesa Member, Mooney Falls Member, Thunder Springs Member, and Whitmore Wash Member.<ref name="Beuss2003a"/><ref name="Chronic1983a">Chronic, H (1983) ''Roadside Geology of Arizona.'' The Mountaineers Books, Seattle, Washington. (softcover, {{ISBN|978-0-87842-147-3}})</ref> Its origins date to the Mississippian age.
Redwall Limestone consists predominately of light-olive-gray to light-gray, thin-bedded, fine- to coarse-grained, thin- to thick-bedded, often cherty, [[limestone]]. Its lower part consists of brownish-gray, interbedded finely crystalline [[dolomite]] and fine- to coarse-grained limestone with layers of white [[chert]] lenses and yellowish-gray and brownish-gray, cliff-forming, thick-bedded, fine-grained dolomite. It is divided into Horseshoe Mesa Member, Mooney Falls Member, Thunder Springs Member, and Whitmore Wash Member.<ref name="Beuss2003a"/><ref name="Chronic1983a">Chronic, H (1983) ''Roadside Geology of Arizona.'' The Mountaineers Books, Seattle, Washington. (softcover, {{ISBN|978-0-87842-147-3}})</ref> Its origins date to the Mississippian age.



Revision as of 14:02, 12 June 2018

Redwall Limestone
Stratigraphic range: Early and early Late Mississippian[1][2]
Redwall Limestone cliff, and upper platform of cliff extension from Tower of Set, central Grand Canyon, adjacent Granite Gorge.
The bottom of Redwall cliffs typically rest on sections of Temple Butte Limestone-(locally), or attached sections of Muav Limestone cliffs (regionally exposed in Grand Canyon, elsewhere in Arizona, not always with surface exposure).
TypeGeological formation
UnderliesSurprise Canyon Formation (Surprise Canyon Formation locally fills paleovalleys, caves, and collapse structures cut into the underlying Redwall Limestone.)
OverliesMuav Limestone and Temple Butte Limestone
Thickness800 feet (240 m), at maximum
Lithology
Primaryfossiliferous limestone
Otherdolomite and chert
Location
RegionNorthern Arizona, southeast California, New Mexico, and southern Utah, Nevada
CountryUnited States of America
Type section
Named forNamed for red appearance of its escarpment on either side of the Grand Canyon.[3]
Named byGilbert (1875)[3]

Redwall Limestone is a resistant cliff-forming unit that forms prominent, red-stained cliffs that range in height from 500 feet (150 m) to 800 feet (240 m), and date to the Mississippian age.

Lithology

Redwall Limestone consists predominately of light-olive-gray to light-gray, thin-bedded, fine- to coarse-grained, thin- to thick-bedded, often cherty, limestone. Its lower part consists of brownish-gray, interbedded finely crystalline dolomite and fine- to coarse-grained limestone with layers of white chert lenses and yellowish-gray and brownish-gray, cliff-forming, thick-bedded, fine-grained dolomite. It is divided into Horseshoe Mesa Member, Mooney Falls Member, Thunder Springs Member, and Whitmore Wash Member.[1][4] Its origins date to the Mississippian age.

Contacts

The upper and lower contacts of the Redwall Limestone are both unconformities. Its upper contact is a disconformity that characteristically is a nearly horizontal surface with little or no relief. Locally, the bottom unconformity of the Redwall Limestone contains a basal conglomerate that directly rests upon this bottom unconformity. This basal conglomerate is typically composed of gravel that is locally derived from either the underlying Temple Butte Limestone or Muav Limestone.

The upper contact of the Redwall Limestone consists of a deeply eroded disconformity characterized by deeply incised paleovalleys and deep paleokarst depressions that are often filled by sediments of the Surprise Canyon Formation.[1][5]

Temple Butte

The "Temple Butte Formation" is a stratigraphic unit in Arizona that dates back to the Chesterian age of the Mississippian epoch of the Carboniferous period.[6]

Grand Canyon

In Grand Canyon National Park marine fish left behind the fossilized remains of their bony plates.[6] In the Grand Canyon, the upper disconformity forms a horizontal platform at the top of the Redwall Limestone.

See also

References

  1. ^ a b c Beus, SS (2003) Redwall Limestone and Surprise Canyon Formation. in: Beus, S.S., Morales, M., eds., pp. 115-134, Grand Canyon Geology, 2nd. Oxford University Press, New York.
  2. ^ Anonymous (2006e) Redwall Limestone. Stratigraphy of the Parks of the Colorado Plateau. U.S. Geological Survey, Reston, Virginia.
  3. ^ a b Gilbert, GK (1875) Chapter 6 Report upon the geology of portions of Nevada, Utah, California, and Arizona. in GM Wheeler, ed., pp. 17-187, Report on the geographical and geological explorations and surveys west of the One hundredth meridian. Publication of the Wheeler Survey, U.S. Geological and Geographical Survey, Washington, DC.
  4. ^ Chronic, H (1983) Roadside Geology of Arizona. The Mountaineers Books, Seattle, Washington. (softcover, ISBN 978-0-87842-147-3)
  5. ^ Kenny, R (2010) Continental paleoclimate estimates from the late Mississippian Redwall karst event: northern and north-central Arizona (USA). Carbonates Evaporites. 25(4):297-302
  6. ^ a b Hunt, ReBecca K., Vincent L. Santucci and Jason Kenworthy. 2006. "A preliminary inventory of fossil fish from National Park Service units." in S.G. Lucas, J.A. Spielmann, P.M. Hester, J.P. Kenworthy, and V.L. Santucci (ed.s), Fossils from Federal Lands. New Mexico Museum of Natural History and Science Bulletin 34, pp. 63–69.

Popular Publications

  • Blakey, Ron and Wayne Ranney, Ancient Landscapes of the Colorado Plateau, Grand Canyon Association (publisher), 2008, 176 pages, ISBN 978-1934656037
  • Chronic, Halka. Roadside Geology of Arizona, Mountain Press Publishing Co., 1983, 23rd printing, pp. 229–232, ISBN 978-0-87842-147-3
  • Lucchitta, Ivo, Hiking Arizona's Geology, 2001, Mountaineers's Books, ISBN 0-89886-730-4

External links