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Geologic Unit: Fuson
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Map showing publication footprint
  • Usage in publication:
    • Fuson formation*
  • Modifications:
    • Named
  • Dominant lithology:
    • Sandstone
    • Shale
  • AAPG geologic province:
    • Chadron arch
    • Williston basin
Publication:

Darton, N.H., 1901, Preliminary description of the geology and water resources of the southern half of the Black Hills and adjoining regions in South Dakota and Wyoming: U.S. Geological Survey Annual Report, 21, pt. 4, p. 489-599.


Summary:

Very fine grained sandstones and massive shales and clay; of white, gray, buff, purple, and maroon colors. Thickness 30-100 ft. Underlies Dakota sandstone as here revised; overlies Minnewaste limestone. Included in Dakota sandstone of previous reports. Striking exposures in Fuson Canyon [on east side of Black Hills, SD], for which it is named. Area is in Meade and Lawrence Cos in the Williston basin, and Pennington, Custer, and Fall River Cos on the Chadron arch. Type section not given. Assigned to the Cretaceous.

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


Map showing publication footprint
  • Usage in publication:
    • Fuson formation*
  • Modifications:
    • Overview
  • AAPG geologic province:
    • Williston basin
Publication:

Darton, N.H., 1904, Comparison of the stratigraphy of the Black Hills, Bighorn Mountains, and Rocky Mountain Front Range: Geological Society of America Bulletin, v. 15, p. 379-448.


Summary:

Fuson formation of Early Cretaceous age in the Black Hills area, SD, Williston basin, resembles a clay assigned to upper part of Cloverly formation, a new unit named in the Bighorn uplift. A new name--Cloverly--defined in the uplift, rather than use of older term Fuson, due to lack of evidence as to the equivalency of the two clays. Correlation diagram.

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


Map showing publication footprint
  • Usage in publication:
    • Fuson shale*
  • Modifications:
    • Revised

Map showing publication footprint
  • Usage in publication:
    • Fuson shale*
  • Modifications:
    • Areal extent
  • AAPG geologic province:
    • Williston basin
    • Chadron arch
Publication:

Dobbin, C.E., and Larsen, R.M., 1934, Geologic and structure contour map of the southern half of the Cedar Creek Anticline, Fallon County, Montana and Bowman County, North Dakota: U.S. Geological Survey [Monograph], Accompanied by DOI Press Memo 94227, p. 2, 1935


Summary:

In subsurface, extended into the Cedar Creek anticline, southeastern MT and southwestern ND, Williston basin and Chadron arch. Is an interval of shale and sandy shale that overlies Lakota sandstone and underlies Fall River sandstone. Age is Early Cretaceous.

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


Map showing publication footprint
  • Usage in publication:
    • Fuson shale*
  • Modifications:
    • Overview
Publication:

Waage, K.M., 1955, Dakota group in northern Front Range foothills, Colorado, IN Shorter contributions to general geology, 1955-57: U.S. Geological Survey Professional Paper, 274-B, p. B15-B51. [Available online from the USGS PubsWarehouse: http://pubs.er.usgs.gov/pubs/pp/pp274B]


Summary:

Correlation with other Cretaceous units in Powder River basin, northeast WY, Wind River basin, central WY and Denver basin, southeast WY, northeast and south-central CO shown on fig 19.

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


Map showing publication footprint
  • Usage in publication:
    • Fuson member*
  • Modifications:
    • Revised
    • Areal extent
    • Overview
  • AAPG geologic province:
    • Chadron arch
Publication:

Waage, K.M., 1959, Stratigraphy of the Inyan Kara group in the Black Hills, IN Contributions to general geology, 1958: U.S. Geological Survey Bulletin, 1081-B, p. B11-B90.


Summary:

Fuson shale is reduced to member status in redefined Lakota formation. Type section (base not exposed) measured in a cliff at apex of sharp bend in Dry Creek, Fuson Canyon, in SE/4 NE/4 SW/4 sec. 36, T. 5 S., R. 6 E., Custer Co., SD, on the Chadron arch. Suggests use of name in limited area where underlying Minnewaste limestone is present. Member is 92 feet thick in an incomplete section measured at the type locality in Fuson Canyon and consists of siltstone, claystone, and sandstone. Is separated from overlying Fall River sandstone by a transgressive unconformity. Minnewaste limestone is not present at type locality. Age is Early Cretaceous.

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


Map showing publication footprint
  • Usage in publication:
    • Fuson member*
  • Modifications:
    • Reference
    • Overview
  • AAPG geologic province:
    • Chadron arch
Publication:

Post, E.V., and Bell, Henry, III, 1961, Chilson Member of the Lakota Formation in the Black Hills, South Dakota and Wyoming; Article 349, IN Geological Survey Research 1961; short papers in the geologic and hydrologic sciences; Articles 293-435: U.S. Geological Survey Professional Paper, 424-D, p. D173-D178.


Summary:

Reference section on east bank of Cheyenne River, in SW/4 NW/4 sec. 2, T. 9 S., R. 4 E., Cascade Springs quadrangle, Fall River Co., SD, on the Chadron arch. At the reference section unconformably overlain by Fall River Formation, and overlies Minnewaste Limestone member of Lakota Formation. Overlaps underlying parts of Lakota Formation northwestward in the Black Hills. Characteristically variegated claystone and siltstone, particularly in the southern and northern Black Hills. White, speckled with red, massive argillaceous fine-grained sandstone commonly in the middle of the member, and a thin, bright-green, clayey sandstone at many localities in the middle of the member. Channel sandstone that is locally conglomeratic comprises much of lower Fuson along the western side of the Black Hills, and cross-bedded conglomeratic sandstone also fills a channel scoured from the top of Fuson part or all the way through the mudstone and massive argillaceous sandstone facies in the southern Black Hills. Polished, well-rounded pebbles of pink quartzite, quartz, and chert are diagnostic of Fuson. Overlaps underlying Chilson Member of Lakota Formation and rests directly on Morrison Formation in the northwestern Black Hills. Assigned to the Early Cretaceous.

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


Map showing publication footprint
  • Usage in publication:
    • Fuson Member*
  • Modifications:
    • Overview
  • AAPG geologic province:
    • Chadron arch
    • Williston basin
    • Powder River basin
Publication:

Gott, G.B., Wolcott, D.E., and Bowles, C.G., 1974, Stratigraphy of the Inyan Kara Group and localization of uranium deposits, southern Black Hills, South Dakota and Wyoming: U.S. Geological Survey Professional Paper, 763, 57 p., (incl. geologic maps, scale 1:48,000)


Summary:

Summarizes lithologic variations and shows distribution of Fuson, upper of three members of Lakota Formation (ascending): Chilson, Minnewaste Limestone, and Fuson Members. Subdivided into six informal units, of which four are mapped and two others shown on a restored section. Discusses variations in the lithology of the member and shows distribution in several 7 1/2 min quads in the southern Black Hills, Fall River and Custer Cos, SD, and Weston Co, WY in Williston and Powder River basins and on Chadron arch. Assigned to the Early Cretaceous.

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


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