U.S. Geological Survey Home AASG Logo USGS HOME CONTACT USGS SEARCH USGS
National Geologic Map Database
Geologic Unit: Sevy
Search archives
Map showing publication footprint
  • Usage in publication:
    • Sevy dolomite*
  • Modifications:
    • Original reference
  • Dominant lithology:
    • Dolomite
  • AAPG geologic province:
    • Great Basin province
Publication:

Nolan, T.B., 1930, Paleozoic formations in the Gold Hill quadrangle, Utah: Washington Academy of Sciences Journal, v. 20, no. 17, p. 421-432.


Summary:

Pg. 421-432. Sevy dolomite. Remarkably homogeneous throughout. Typical rock a well-bedded light mouse-gray dolomite in layers 6 to 12 inches thick, which weathers very light gray; extremely dense; breaks with conchoidal fracture; most beds show faint lamination parallel to bedding. The formation contains a few beds of darker dolomite near top and locally beds containing tiny nodules of light-colored chert. Basal bed is conglomeratic. Thickness 450 +/- feet. No diagnostic fossils. Overlies, unconformably, Laketown dolomite, of Silurian age.
Named from exposures in Sevy Canyon, on west side of Deep Creek Range, Gold Hill district, [Gold Hill quadrangle, Tooele Co.], western UT.
[See also Nolan's USGS Prof. Paper 177, 1935.]

Source: GNU records (USGS DDS-6; Denver GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Sevy dolomite*
  • Modifications:
    • Areal extent
  • AAPG geologic province:
    • Great Basin province
Publication:

Staatz, M.H., and Osterwald, F.W., 1959, Geology of the Thomas Range fluorspar district, Juab County, Utah: U.S. Geological Survey Bulletin, 1069, 97 p., (incl. geologic maps, scale 1:12,000 and 1:6,000)


Summary:

Pg. 8, 29-31, pl. 1. Sevy dolomite. Described in Juab County, Utah, where it is 1,122 feet thick; overlies Thursday dolomite (new) and underlies Simonson dolomite and Guilmette formations, undifferentiated. [Age is Devonian.]
[Measured section: at point 5,540 ft N. 78 deg. W. of the Oversight mine, in T. 12 S., R. 12 W., Juab Co., western UT.]

Source: US geologic names lexicon (USGS Bull. 1200, p. 3537); supplemental information from GNU records (USGS DDS-6; Denver GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Sevy Dolomite*
  • Modifications:
    • Age modified
  • AAPG geologic province:
    • Great Basin province

Map showing publication footprint
  • Usage in publication:
    • Sevy Dolomite*
  • Modifications:
    • Age modified
    • Revised
  • AAPG geologic province:
    • Great Basin province
Publication:

Hintze, L.F., 1980, Preliminary geologic map of the Fish Springs NW and Fish Springs SW quadrangles, Juab and Tooele Counties, Utah: U.S. Geological Survey Miscellaneous Field Studies Map, MF-1148, 1 sheet, scale 1:24,000


Summary:

Assigned Early Devonian age in Fish Springs Range, Juab Co, UT, Great Basin province. Age probably based on stratigraphic position. Overlies [unconformably] Middle Silurian Thursday Member (rank reduced) of Laketown Dolomite; underlies Middle Devonian Simonson Dolomite.

Source: GNU records (USGS DDS-6; Denver GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Sevy Dolostone*
  • Modifications:
    • [Redefined]
  • Dominant lithology:
    • Dolostone
  • AAPG geologic province:
    • Great Basin province
Publication:

Van Loenen, R.E., 1987, Geologic map of the Mount Grafton Wilderness Study Area, Lincoln and White Pine Counties, Nevada: U.S. Geological Survey Miscellaneous Field Studies Map, MF-1938, 1 sheet, scale 1:50,000


Summary:

Sevy Dolostone. [Redefined; dolostone is a more appropriate term than dolomite (mineral name).] Is chiefly medium- to light-gray, aphanitic dolostone in beds 3 to 5 feet thick. Weathers light-gray and splits into blocky, angular fragments. A thin bed of fine- to medium-grained quartz sandstone occurs near top. Total thickness about 800 feet. Overlies Laketown Dolostone (Middle and Upper Silurian). Resembles the aphanitic dolostone of overlying Simonson (Middle Devonian). Age is Early and Middle Devonian.
Not separately mapped. Mapped undifferentiated with Simonson Dolostone.

Source: Publication; supplemental information from GNU records (USGS DDS-6; Denver GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Sevy Dolostone*
  • Modifications:
    • Age modified

Map showing publication footprint
  • Usage in publication:
    • Sevy Dolostone*
  • Modifications:
    • Redescribed
  • Dominant lithology:
    • Dolostone
  • AAPG geologic province:
    • Great Basin province
Publication:

Poole, F.G., Stewart, J.H., Palmer, A.R., Sandberg, C.A., Madrid, R.J., Ross, R.J., Jr., Hintze, L.F., Miller, M.M., and Wrucke, C.T., 1992, Latest Precambrian to latest Devonian time; development of a continental margin, Chapter 2, IN Burchfiel, B.C., Lipman, P.W., and Zoback, M.L., eds., The Cordilleran Orogen; conterminous United States: Geological Society of America, The Geology of North America, The Decade of North American Geology (DNAG), v. G-3, p. 9-56.


Summary:

Is redescribed as dolostone. The name "dolostone" is used for rocks composed predominantly of the mineral "dolomite" on Figure 2 and throughout this chapter, although in the literature it has been common practice to use dolomite rather than dolostone in formal names of dolomitic formations and members. Occurs in stratigraphic column for west-central UT (Great Basin province); conformably above unnamed Upper Silurian dolostone; unconformably below Simonson Dolostone (redescribed) (Middle Devonian). In stratigraphic column for east-central NV (Great Basin province); conformably above unnamed Upper Silurian dolostone; unconformably below McColley Canyon Formation (Lower Devonian). Assigned to Lochkovian and Pragian (Lower Devonian).

Source: GNU records (USGS DDS-6; Denver GNULEX).


Map showing publication footprint
  • Usage in publication:
    • Sevy Dolomite*
  • Modifications:
    • Age modified
  • AAPG geologic province:
    • Great Basin province
Publication:

Ketner, K.B., 1997, Geologic maps showing structural modes in the Goshute Mountains and Toano Range, Elko County, Nevada: U.S. Geological Survey Miscellaneous Investigations Series Map, I-2546, 1 sheet, scale 1:24,000


Summary:

Age of the Sevy Dolomite in this area (Silver Zone basin area, Johnson Canyon area) is here revised [from Early Devonian] to: Early and Middle Devonian [based on regional stratigraphic relations].

Source: GNU records (USGS DDS-6; Menlo GNULEX).


Search archives

For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

Asterisk (*) indicates published by U.S. Geological Survey authors.

"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).

Slash (/) indicates name conflicts with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005, 2021). May be explained within brackets ([ ]).