Crystal Peak Dolomite

Crystal Peak Dolomite
Stratigraphic range: Middle Ordovician (Whiterockian) ~471–458  Ma PreꞒ Ꞓ O S D C P T J K Pg N
Type	Formation
Underlies	Eureka Quartzite
Overlies	Watson Ranch Quartzite
Thickness	up to 92 ft (28 m)
Lithology
Primary	dolomite
Other	Limestone
Location
Coordinates	38°48′N113°36′W / 38.8°N 113.6°W / 38.8; -113.6
Approximate paleocoordinates	8°06′S79°48′W / 8.1°S 79.8°W / -8.1; -79.8
Region	Utah
Country	United States
Extent	Wah Wah Mountains
Type section
Named for	Crystal Peak section
Crystal Peak Dolomite (the United States) Show map of the United States Crystal Peak Dolomite (Utah) Show map of Utah

The Crystal Peak Dolomite is a geologic formation in the Wah Wah Mountains of western Utah. It preserves fossils dating to the Middle Ordovician period. ^[1]

Background

This geographic stratum is named for its dolomite (used to describe a sedimentary carbonate rock composed predominantly of the mineral dolomite). It is named for exposures at the Crystal Peak section 10 miles (16 km) southwest of Smooth Canyon, Millard County, Utah in the Great Basin province. It separates the Watson Ranch Quartzite tongue of Swan Peak Quartzite from the younger Eureka Quartzite. The stratum generally consists of brown, gray to black, usually fine- to medium-grained, but may be coarse-grained, dolomite. Thin [about 6 feet (1.8 m) thick] quartz sandstone and siltstone occur about 50 feet (15 m) from base. The layer is 85 feet (26 m) thick in Smooth Canyon. The stratum is fossiliferous and it has been shown to contain orthocone cephalopods and corals identified as Eofletcheria sp. . ^{[1] [2]} The thickness has been measured between 61 feet (19 m) thick in Tule Valley, Utah to 92 feet (28 m) thick in Desert Range Experiment Station, Utah; it is 89 feet (27 m) thick at Crystal Peak. It is classified as Middle Ordovician age. The Crystal Peak equivalent has been recognized in the Lehman Formation in the Snake Range of Nevada, but was not specifically identified in adjoining eastern Nevada.

See also

• Geology portal
• Utah portal

• List of fossiliferous stratigraphic units in Utah
• Paleontology in Utah

References

1. Crystal Peak Dolomite at Fossilworks.org
2. Hintze, 1951

Bibliography

• L.F. Hintze. 1951. Lower Ordovician detailed stratigraphic sections for western Utah. Utah Geological and Mineralogical Survey Bulletin 39:99

External links

• G. W. Webb (1956). "National Geologic Map Database" . Retrieved 13 January 2016.
• American Association of Petroleum Geologists; Shell Exploration & Production (20 January 2013). The Great American Carbonate Bank (Memoir 98). ISBN   9780891813804 . Retrieved 13 January 2016.