GEOLEX

Summary of Citation: Benton

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

Usage in Publication:
Benton group*

Modifications:	Geologic Province:	Dominant Lithology:
Revised	Williston basin Chadron arch Powder River basin

Summary:
Revised and used in the Black Hills, WY and SD in Williston and Powder River basins and on Chadron arch, to include (ascending): Graneros shale, Greenhorn limestone, and Carlile formation. Overlies Dakota formation; underlies Niobrara formation. Late Cretaceous in age.

Summary of Citation: Benton

Publication:
Willis, Bailey, 1902, Stratigraphy and structure, Lewis and
   Livingston ranges, Montana: Geological Society of America
   Bulletin, v. 13, p. 305-352

Usage in Publication:
Benton shale*

Modifications:	Geologic Province:	Dominant Lithology:
Areal limits	Sweetgrass arch

Summary:
Recognized west of Saint Mary Lakes, Glacier Co, MT on the Sweetgrass arch. Contains fossils classed as "Benton" forms (ammonites, etc.). Underlies Kennedy gravels or formation (new). Is of Cretaceous age.

Summary of Citation: Benton

Publication:
Wegemann, C.H., 1911, The Salt Creek oil field, Natrona County,
   Wyoming, IN Woodruff, E.G., and Wegemann, C.H., The Lander
   and Salt Creek oil fields, Wyoming: U.S. Geological Survey
   Bulletin, 452, p. 37-83

Usage in Publication:
Benton shale*

Modifications:	Geologic Province:	Dominant Lithology:
Revised	Wind River basin

Summary:
Divided into (ascending): an unnamed shale at base, 270 ft thick; Mowry shale member, 300 ft thick; unnamed shale, 800 ft thick; Wall Creek sandstone lentil (new), 80 ft thick; and an unnamed shale, 220 ft thick. Overlies Dakota? sandstone. Underlies Niobrara shale. Is the lower of two formations of the Colorado group. Late Cretaceous age. Salt Creek oil field is located in Ts38 to 41N, Rs78 to 79W, Natrona Co, WY in the Wind River basin.

Summary of Citation: Benton

Publication:
Barnett, V.H., 1914, Possibilities of oil in the Big Muddy dome,
   Converse and Natrona Counties, Wyoming, IN Contributions to
   economic geology, 1913; Part 2, Mineral fuels: U.S. Geological
   Survey Bulletin, 581-C, p. 105-117

Usage in Publication:
Benton shale*

Modifications:	Geologic Province:	Dominant Lithology:
Revised	Powder River basin Wind River basin

Summary:
Benton shale mapped at southwest and south central part of geologic map in Natrona Co (Wind River basin) and in Converse Co (Powder River basin), WY. Overlies Cloverly formation which was not mapped. Underlies Niobrara formation. Divided into a lower thick dark soft shale that is overlain in sequence by dark hard shale, Mowry shale member, shale, Wall Creek sandstone member (formerly designated Wall Creek sandstone lentil), and a dark shale. Is about 1,000 ft thick. Fossiliferous. A sandstone about 320 ft below the Wall Creek contains the marine fossil plant HALYMENITES MAJOR Lesquereux. Of Late Cretaceous age.

Summary of Citation: Benton

Publication:
Hintze, F.F., Jr., 1915, The Basin and Greybull oil and gas
   field, Bighorn County, Wyoming: Wyoming Geological Survey
   Bulletin, no. 10, 62 p.

Usage in Publication:
Benton shale

Modifications:	Geologic Province:	Dominant Lithology:
Revised	Bighorn basin

Summary:
Divided into (ascending): "Lower Benton shale member," Peay sandstone member, "Upper Benton shale member," Torchlight sandstone member. Peay and Torchlight are newly named. Benton belongs to Colorado group. Benton overlies Cloverly sandstone and underlies Basin shale (first used), upper formation of Colorado Group. Geologic map of the Basin-Greybull area, Bighorn Co., WY in the Bighorn basin. Of Late Cretaceous age. History of nomenclature chart.

Summary of Citation: Benton

Publication:
Darton, N.H., 1919, Description of the Newell quadrangle, South
   Dakota: U.S. Geological Survey Geologic Atlas of the United
   States, Newell folio, no. 209, 7 p.

Usage in Publication:
Benton group

Modifications:	Geologic Province:	Dominant Lithology:
Not used

Summary:
Discontinued use in the Black Hills region of SD and WY, Williston and Powder River basins and on the Chadron arch. Formations comprising the group incorporated into the more inclusive Colorado group.

Summary of Citation: Benton

Publication:
Mather, K.F., Gilluly, James and Lusk, R.G., 1928, Geology and
   oil and gas prospects of northeastern Colorado, IN Contributions
   to economic geology, 1927; Part 2, Mineral fuels: U.S.
   Geological Survey Bulletin, 796-B, p. B65-B124

Usage in Publication:
Benton shale*

Modifications:	Geologic Province:	Dominant Lithology:
Overview Revised	Denver basin

Summary:
Consists of marine shale. Lies above Dakota group and below Niobrara formation. Is equivalent to Graneros, Greenhorn, and Carlile formations of southern CO and eastern WY. Mapped (geologic map) as a narrow outcrop from vicinity of Lyons, CO north to T11N, R69W in Boulder and Larimer Cos in the Denver basin. Consists of dark-gray shale and shaly sandstone in the lower part. Upper part revised in that the uppermost 3-20 ft thick gray, fine-grained, massive, soft shaly sandstone assigned to the Codell sandstone member. Codell is thus reassigned from Carlile shale as in KS, is geographically extended into east CO where it is reassigned to the Benton as its uppermost member. Measured section.

Summary of Citation: Benton

Publication:
Thom, W.T., Jr. and Spieker, E.M., 1931, The significance of
   geologic conditions in Naval Petroleum Reserve No. 3 , Wyoming:
   U.S. Geological Survey Professional Paper, 163, 64 p.

Usage in Publication:
Benton shale

Modifications:	Geologic Province:	Dominant Lithology:
Not used

Summary:
Nomenclature applied to Upper Cretaceous rocks above the Cloverly formation and beneath the Niobrara shale by Wegemann (1918, USGS Bulletin 670) modified in this report on the Salt Creek oil field, U. S. Naval Petroleum Reserve No. 3, Natrona Co., WY in the Wind River basin. Term Benton shale not used. The Mowry shale member of the Benton raised in stratigraphic rank to Mowry shale. The Wall Creek sandstone member of the Benton is reassigned as the Wall Creek sandstone member, upper member of the Frontier formation. Therefore, rocks formerly assigned to the Benton are designated (ascending order): 1.) Thermopolis shale (formerly an unnamed basal part of the Benton), 2.) Mowry shale, 3.) Frontier formation which is divided into an unnamed part and the Wall Creek sandstone member, and 4.) Carlile shale (formerly the upper unnamed part of the Benton. Nomenclature chart. Columnar section.

Summary of Citation: Benton

Publication:
Kline, V.H., 1942, Stratigraphy of North Dakota: American
   Association of Petroleum Geologists Bulletin, v. 26, no. 3,
   p. 336-379

Usage in Publication:
Benton formation

Modifications:	Geologic Province:	Dominant Lithology:
Areal limits	Williston basin

Summary:
Name used in subsurface in ND in Williston basin. In eastern ND falls rather easily into three distinct subdivisions: a lower, dark-gray, noncalcareous, only slightly fossiliferous shale; a middle, light-gray, highly fossiliferous limestone or calcareous shale; and an upper, dark-gray, noncalcareous, only slightly fossiliferous shale. This tripartite division suggests a possible correlation with the Carlile, Greenhorn, and Graneros formations (descending), into which the Benton has been divided in SD and WY. As much as 750 ft thick. Underlain by Dakota sandstone; overlain by Niobrara formation. Cretaceous in age.

Summary of Citation: Benton

Publication:
Laird, W.M. and Towse, D.F., 1951, Stratigraphy of North Dakota
   with reference to oil possibilities: North Dakota Geological
   Survey Report of Investigations, no. 2, 2 sheets, Revised.

Usage in Publication:
Benton formation

Modifications:	Geologic Province:	Dominant Lithology:
Revised	Williston basin

Summary:
Includes Greenhorn limestone and "Muddy sand" members in the Williston basin, ND. Overlain by Niobrara formation; underlain by Dakota sandstone. Basal formation of Colorado stage [group]. Cretaceous in age.

Summary of Citation: Benton

Publication:
Cobban, W.A. and Reeside, J.B., Jr., 1952, Correlation of the
   Cretaceous formations of the Western Interior of the United
   States: Geological Society of America Bulletin, v. 63, no.
   10, p. 1011-1043

Usage in Publication:
Benton formation*

Modifications:	Geologic Province:	Dominant Lithology:
Overview	Williston basin

Summary:
Name used in Williams Co and the Bismarck region, northwestern and central SD, respectively, in subsurface of Williston basin. Overlain conformably by Niobrara formation; underlain conformably by Dakota sandstone. Late Cretaceous (Cenomanian, Turonian, and early Coniacian) in age. Correlated with (ascending): Graneros, Greenhorn, and Carlile formations of Ward Co, north-central ND.

Summary of Citation: Benton

Publication:
Hansen, D.E., 1955, Subsurface correlations of the Cretaceous
   Greenhorn-Lakota interval in North Dakota: North Dakota
   Geological Survey Bulletin, no. 29

Usage in Publication:
Benton shale

Modifications:	Geologic Province:	Dominant Lithology:
Not used

Summary:
Discontinues use of name in Williston basin in ND.

Summary of Citation: Benton

Publication:
Van Horn, Richard, 1957, Bedrock geology of the Golden quadrangle,
   Colorado: U.S. Geological Survey Geologic Quadrangle Map,
   GQ-103, 1 sheet, scale 1:24,000

Usage in Publication:
Benton shale*

Modifications:	Geologic Province:	Dominant Lithology:
Mapped 1:24k (Golden quad, Jefferson Co, CO)	Denver basin	Shale Siltstone Limestone Bentonite

Summary:
Is Lower Cretaceous formation mapped in northern Jefferson Co, CO (Denver basin). Conformably overlies Dakota group (Lower Cretaceous); unconformably underlies Niobrara formation (Upper Cretaceous). Outcrops as narrow northwest striking band in southwestern and western parts of quad; cut by Golden fault south of Tucker Gulch. Consists mainly of shale interbedded with bentonite, siltstone, and limestone. Well exposed along bank of Ralston Reservoir where equivalents of Carlile shale, Greenhorn limestone, and Graneros shale are recognizable. At reservoir also possible to recognize equivalents of Lincoln limestone, Hartland shale, and Bridge Creek limestone members of Greenhorn. Contains fossils INOCERAMUS, KANABICERAS, and shark teeth. Thickness is about 500 ft.

Summary of Citation: Benton

Publication:
Taylor, R.B., 1975, Geologic map of the Bottle Pass quadrangle,
   Grand County, Colorado: U.S. Geological Survey Geologic
   Quadrangle Map, GQ-1224, 1 sheet, scale 1:24,000

Usage in Publication:
Benton Formation*

Modifications:	Geologic Province:	Dominant Lithology:
Overview	North Park basin

Summary:
Is Upper and Lower Cretaceous formation mapped in central part of quadrangle, Grand Co., CO (North Park basin). Overlies Dakota Sandstone (Lower Cretaceous); overlain by Niobrara Formation (Upper Cretaceous). Map unit described as gray to dark-gray fissile to subfissile silty shale and claystone; dark-brown limestone is underlain by well-indurated fine-grained sandstone in uppermost 10 ft of unit; lower part contains beds of fine-grained sandstone intercalated with dark-gray shale. Unit is potentially unstable and highly susceptible to slump and landsliding. Thickness about 450 ft, but thinned or thickened drastically near major folds and faults.

Summary of Citation: Benton

Publication:
Cobban, W.A., 1988, Tarrantoceras Stephenson and related ammonoid
   genera from Cenomanian (Upper Cretaceous) rocks in Texas and
   the Western Interior of the United States: U.S. Geological
   Survey Professional Paper, 1473, 51 p.

Usage in Publication:
Benton Shale*

Modifications:	Geologic Province:	Dominant Lithology:
Biostratigraphic dating	North Park basin

Summary:
Is formation in north-central CO. Is assigned (in part) an early late Cenomanian (Late Cretaceous) age based on presence of the ammonites NEOCARDIOCERAS UPTONENSE, N. LAEVIGATUM, and N. MINUTUM from USGS Mesozoic localities D7388, D7389, D7390, D7395, D7402, and D7403, Grand Co, CO in North Park basin. Collections range from 64.3 m-38.4 m below base of Juana Lopez Member.