USGS Visual Identifier

GEOLEX

Summary of Citation: Dry Creek

Publication:
Peale, A.C., 1893, The Paleozoic section in the vicinity of
   Three Forks, Montana, with petrographic notes by G.P. Merrill:
   U.S. Geological Survey Bulletin, 110, 56 p.
Usage in Publication:
Dry Creek shales*

Modifications: Geologic Province: Dominant Lithology:
 First used
 Montana folded belt province
 Shale

Summary:
Is an unranked unit in the Cambrian Gallatin formation in Montana folded belt province, that lies above the mottled limestones and below the pebbly limestones. Is composed of non-fossiliferous shales or shaly calcareous sandstones. Most outcrops are poor, best exposures are on Dry Creek where Dry Creek is 30 ft thick and is brownish yellow, red and pink, sacchariodal in structure, breaks into thin laminae with streaks and seams of calcite. Mapped with Gallatin north of East Gallatin River in Dry Creek (T1N, R4E), Gallatin Co, MT. Neither source of geographic name nor type locality stated. Assigned to the Cambrian.
Summary of Citation: Dry Creek

Publication:
Weed, W.H., 1899, Description of the Fort Benton quadrangle
   [Montana]: U.S. Geological Survey Geologic Atlas of the United
   States, Fort Benton folio, no. 55, 7 p.
Usage in Publication:
Dry Creek shale*

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

Summary:
Mapped (geologic map) in southwest part of quad in Little Belt Mountains, Cascade Co, MT, Sweetgrass arch, as one of seven units of Barker formation (first used). [Use of Barker was a mapping convenience as constituent units were not mappable at scale used; Barker probably not intended to be of group rank]. Consists of brick-red shales and limestones. Overlies Pilgrim limestone (first used) of Barker; underlies Yogo limestone (first used) of Barker. Barker contains middle Cambrian fossils.
Summary of Citation: Dry Creek

Publication:
Weed, W.H., 1900, Geology of the Little Belt Mountains, Montana:
   U.S. Geological Survey Annual Report, 20, pt. 3, p. 257-462
Usage in Publication:
Dry Creek shale*

Modifications: Geologic Province: Dominant Lithology:
 Overview
Revised
Age modified
 Sweetgrass arch
 

Summary:
Removed from Barker formation and raised to formation rank (though mapped as one of seven units of Barker). Unit is consistent throughout central MT, though as it weathers easily, it is seldom well exposed. Good sections observed in Little Belt Mountains, MT, Sweetgrass arch, at head of King Creek, near Yogo, in Big Park on Belt Creek above Monarch, and on Pilgrim Creek. Consists of brick-red and bright-yellow sandy shale. Average thickness is 40 ft. Overlies Pilgrim limestone (revised); underlies Yogo limestone (revised). Correlation of measured sections. Age revised from Late Cambrian to Middle Cambrian based on trilobites identified by Walcott in overlying and underlying units.
Summary of Citation: Dry Creek

Publication:
Deiss, Charles, 1936, Devonian rocks in the Big Snowy Mountains,
   Montana: Journal of Geology, v. 44, no. 5, p. 639-644
Usage in Publication:
Dry Creek shale

Modifications: Geologic Province: Dominant Lithology:
 Areal limits
 Central Montana uplift
 

Summary:
Tentatively extended into Big Snowy Mountains, Fergus Co, MT, Central Montana uplift. At Half Moon Pass section, unit is 32 ft thick. Overlies Pilgrim limestone; disconformably underlies Three Forks shale. Late Cambrian age.
Summary of Citation: Dry Creek

Publication:
Deiss, C.F., 1936, Revision of type Cambrian formations and
   sections of Montana and Yellowstone National Park: Geological
   Society of America Bulletin, v. 47, no. 8, p. 1257-1342
Usage in Publication:
Dry Creek shale

Modifications: Geologic Province: Dominant Lithology:
 Revised
Overview
 Montana folded belt province
Sweetgrass arch
Central Montana uplift
Yellowstone province
 Shale
Limestone

Summary:
Exposure described by Weed (1900) at Yogo Gulch, Judith Basin Co, MT, Sweetgrass arch in Little Belt Mountains, here designated as type section for Dry Creek. At type (sec 1, T13N, R10E), Dry Creek is 50 ft thick; Weed's original section is 25 ft. Unit thins east and west from its maximum thickness of 99 ft at Belt Creek, Little Belt Mountains; is 32 ft thick in Big Snowy Mountains; not present at Beaver Creek, Big Belt Mountains; averages 68 ft thick. At type, lower fourth is green and chocolate-maroon, argillaceous, calcareous, fossiliferous shale interbedded with gray, thin-bedded limestone; middle half is dark-maroon, dolomitic, sandy mudstone interbedded with buff and mottled dolomitic limestone; upper fourth is bright-buff dolomite and gray fine-grained limestone. Overlies Pilgrim limestone (revised); underlies Devonian limestone. Weed's original section placed his Cambrian Yogo limestone above Dry Creek, however, Devonian SPIRIFER found within one foot above top of Dry Creek at Dry Wolf Creek section, Little Belt Mountains. No Cambrian rocks occur above Dry Creek in Little Belt Mountains, therefore, Yogo has no basis and should be discarded. Additional sections remeasured in central and southern MT within Sweetgrass arch, Montana folded belt province, Central Montana uplift and Yellowstone Park, Yellowstone province. Contains trilobites. Correlation chart. Is uppermost Upper Cambrian unit in study area.
Summary of Citation: Dry Creek

Publication:
Dorf, E. and Lochman, Christina, 1940, Upper Cambrian formations
   in southern Montana: Geological Society of America Bulletin,
   v. 51, no. 4, p. 541-556
Usage in Publication:
Dry Creek shale

Modifications: Geologic Province: Dominant Lithology:
 Not used
   

Summary:
At Deiss' (1936) Crowfoot Ridge section, located in southern part of Gallatin Range within Yellowstone National Park, WY, Yellowstone province, unit called Dry Creek shale represents lower part of Snowy Range formation (new) and, therefore, Dry Creek not used and is replaced by Snowy Range.
Summary of Citation: Dry Creek

Publication:
Lochman, Christina and Duncan, D.C., 1944, Early Upper Cambrian
   faunas of central Montana: Geological Society of America
   Special Paper, 54, 181 p.
Usage in Publication:
Dry Creek shale

Modifications: Geologic Province: Dominant Lithology:
 Areal limits
Revised
Not used
 Montana folded belt province
Sweetgrass arch
 

Summary:
Limited to area of Big Belt Mountains and Bridger Range on west to Little Belt Mountains on east in various counties of central MT within Montana folded belt province and Sweetgrass arch. Restricted to beds of red and yellow platy dolomites, dolomitic mudstones, and some overlying buff or gray dolomites and limestones. Pebble conglomerates described by Deiss (1936) here reassigned as transition zone to underlying Pilgrim formation. Revised Dry Creek has no fossils and is 20-60 ft thick. In westernmost section, Lower Beaver Creek in Big Belt Mountains, Dry Creek absent due to post-Cambrian-pre-Devonian erosion. At easternmost section, Half Moon Pass in Big Snowy Range, absent due to nondeposition. Unconformably underlies Devonian Jefferson dolomite. Only at Upper Beaver Creek section has good evidence of a physical break been found; elsewhere Jefferson-Dry Creek boundary arbitrarily placed at base of first thick-bedded, chocolate-brown, strongly petroliferous limestones typical of Jefferson. Rocks tentatively assigned by Deiss (1936) to Dry Creek at Mount Helena section (Deiss' Grizzly and Oro Fino Gulches section), west of Big Belt Mountains, Lewis and Clark Co, MT. Rocks reassigned to Red Lion formation due to similarity to Red Lion in Philipsburg area, Granite Co, MT. Assignment to Upper Cambrian based on stratigraphic position.
Summary of Citation: Dry Creek

Publication:
Knechtel, M.M., Brockunier, S.R. and Hobbs, S.W., 1944, Plains
   adjacent to the Little Rocky Mountains, Montana: U.S. Geological
   Survey Oil and Gas Investigations Map, OM-4, 1 sheet, scale
   1:48,000
Usage in Publication:
Dry Creek shale*

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

Summary:
Name extended to Little Rocky Mountains region, Blaine and Phillips Cos, MT in Williston basin, for a sequence 60 ft thick of variegated, thinly bedded dolomite, intraformational conglomerate, and shale. Formerly included in the Deadwood formation in the Little Rocky Mountains, MT by Collier and Cathcart (1922). Overlain by Bighorn limestone; underlain by unnamed Cambrian rocks. Cambrian in age.
Summary of Citation: Dry Creek

Publication:
Sloss, L.L. and Laird, W.M., 1947, Devonian System in central
   and northwestern Montana: American Association of Petroleum
   Geologists Bulletin, v. 31, no. 8, p. 1404-1430
Usage in Publication:
Dry Creek shale

Modifications: Geologic Province: Dominant Lithology:
 Revised
 Montana folded belt province
 

Summary:
Restricts unit to glauconitic, micaceous and sandy shales that bear trilobite fragments and phosphatic brachiopods and are associated with flat-pebble conglomerates. Non-micaceous and less fissile shales and mudstones interbedded with rocks of Devonian type which were grouped with Dry Creek by other workers are here referred to as "basal Devonian unit" or "beds of undetermined age" (transitional between Dry Creek and basal Devonian unit). Thickness is variable in Three Forks area, Montana folded belt province, due to erosion. Thickness is 45 ft at measured section at Logan, MT (sec 24, T2N, R2E); on Dry Creek, 10 mi northeast of Logan section, Peale (1893) measured 100 ft of what he referred to as pebbly limestones, but is here considered to be Dry Creek. Overlies Pilgrim limestone; underlies beds of undetermined age. Late Cambrian age.
Summary of Citation: Dry Creek

Publication:
Lochman, Christina, 1950, Status of Dry Creek shale of central
   Montana: American Association of Petroleum Geologists Bulletin,
   v. 34, no. 11, p. 2200-2222
Usage in Publication:
Dry Creek shale member

Modifications: Geologic Province: Dominant Lithology:
 Overview
Revised
 Montana folded belt province
 

Summary:
Rank reduced and assigned to Snowy Range formation as lower of two members. Study area is in Horseshoe Hills area between Logan and Dry Creek, Gallatin Co, MT, Montana folded belt province. Traces history of usage of name; recommends using name as it was originally defined by Peale (1893, U.S. Geological Survey Bulletin 110). Thickness is 35-60 ft in Horseshoe Hills area increasing to 80-95 ft in southern MT. Overlies Maurice formation; underlies Sage pebble-conglomerate member (new) of Snowy Range. Chart showing comparison of published sections from Horseshoe Hills by various authors. Late Cambrian age.
Summary of Citation: Dry Creek

Publication:
Sloss, L.L. and Moritz, C.A., 1951, Paleozoic stratigraphy of
   southwestern Montana: American Association of Petroleum
   Geologists Bulletin, v. 35, no. 10, p. 2135-2169
Usage in Publication:
Dry Creek shale

Modifications: Geologic Province: Dominant Lithology:
 Not used
   

Summary:
Red Lion formation used in place of Dry Creek shale in extreme southwest MT. Study area is south of Boulder batholith and west of Yellowstone National Park within parts of Beaverhead, Madison and Gallatin Cos, MT, Montana folded belt province. Authors prefer to use nomenclature used in Philipsburg quad, located to north of study area, for Upper Cambrian carbonate rocks.
Summary of Citation: Dry Creek

Publication:
Hanson, A.M., 1952, Cambrian stratigraphy in southwestern Montana:
   Montana Bureau of Mines and Geology Memoir, no. 33, 46 p.
Usage in Publication:
Dry Creek shale member

Modifications: Geologic Province: Dominant Lithology:
 Overview
Revised
Areal limits
 Montana folded belt province
 

Summary:
Assigned to Red Lion formation as lower of two members. Unit is valid from Phillipsburg, Granite Co, to Madison Range, Madison Co, MT, Montana folded belt province. Conformably overlies Pilgrim formation; conformably underlies Sage limestone member. Locally missing at Camp, Whitetail and Jourdain Creeks. Up to 20 ft thick. Measured sections. Correlation chart. Late Cambrian age.
Summary of Citation: Dry Creek

Publication:
Shaw, A.B. and McGrew, P.O., 1954, Correlation of the pre-Quaternary
   formations of Wyoming; Chart II: Wyoming Geological Association
   Field Conference Guidebook, no. 9
Usage in Publication:
Dry Creek shale

Modifications: Geologic Province: Dominant Lithology:
 Revised
 Yellowstone province
Greater Green River basin
Bighorn basin
Wind River basin
 

Summary:
Gallatin formation raised to group rank and its members raised to formation rank in footnote in Chart II. Includes (ascending): Dunoir [sic] limestone (Dresbachian), Dry Creek shale (early Franconian), and Sage limestone (middle to late Franconian). Gallatin overlies Park shale (rank raised) of Gros Ventre group (rank raised). Gallatin unconformably underlies Darwin sandstone. This nomenclature is used from Jackson Hole in Yellowstone province, in southwest WY, Greater Green River basin, in the Bighorn and Wind River basins. Only the Sage limestone is present in eastern Bighorn basin.
Summary of Citation: Dry Creek

Publication:
Shaw, A.B. and Deland, C.R., 1955, Cambrian of southwestern
   Wyoming, IN Camp, R.J., chairman, Green River basin: Wyoming
   Geological Association Field Conference Guidebook, no. 10,
   p. 38-42
Usage in Publication:
Dry Creek shale member

Modifications: Geologic Province: Dominant Lithology:
 Revised
 Yellowstone province
Greater Green River basin
Wind River basin
 

Summary:
Reassigned as the basal member of the Open Door limestone (named) of the Gallatin group in Teton Co, WY in the Yellowstone province, in Sublette Co, WY in the Greater Green River basin, and in Fremont Co, WY in the Wind River basin. Overlies Du Noir limestone of Gallatin group. Name Dry Creek applied to the weak reentrant-forming part of the Open Door. The Dresbachian-Franconian boundary lies within the Dry Creek.
Summary of Citation: Dry Creek

Publication:
McMannis, W.J., 1955, Geology of the Bridger Range, Montana:
   Geological Society of America Bulletin, v. 66, no. 11, p.
   1385-1430
Usage in Publication:
Dry Creek shale member

Modifications: Geologic Province: Dominant Lithology:
 Areal limits
 Montana folded belt province
 

Summary:
Extended into Bridger Range, Gallatin Co, MT, Montana folded belt province, as lower member of Snowy Range formation. Thickness ranges from 42 ft at Bridger Peak to 76 ft southwest of Baldy Mountain. Overlies Maurice formation; underlies Sage pebble-conglomerate member of Snowy Range. Snowy Range mapped undivided with Maurice and Maywood? formations. Stratigraphic chart. No fossils found in Dry Creek. Late Cambrian age.
Summary of Citation: Dry Creek

Publication:
Knechtel, M.M., 1956, Emerson formation of Cambrian and probably
   Early Ordovician age in Little Rocky Mountains, Montana:
   American Association of Petroleum Geologists Bulletin, v.
   40, no. 8, p. 1994-1995
Usage in Publication:
Dry Creek shale*

Modifications: Geologic Province: Dominant Lithology:
 Not used
   

Summary:
Name not used in Little Rocky Mountains, Blaine and Phillips Cos, MT in Williston basin. Emerson formation (new) proposed for rocks lying between Flathead sandstone and Bighorn dolomite, including the part formerly referred by Knechtel (1944) as the Dry Creek shales.
Summary of Citation: Dry Creek

Publication:
Shaw, A.B., 1957, Cambrian of the southwestern Wind River basin,
   Wyoming: Wyoming Geological Association Field Conference
   Guidebook, no. 12, p. 8-16
Usage in Publication:
Dry Creek shale member

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

Summary:
Classified as the basal member of the Open Door limestone of the Gallatin Group. Consists of 20 to 50 ft of dark green to black, soft shale with a few 1-2 inch beds of gray or brown, medium crystalline limestone. Overlies Dunoir (spelled Du Noir in author's 1955 report) limestone. Basal contact sharp; upper Dunoir surface is erosional. On surface Dry Creek weathers out to a re-entrant beneath a limestone cliff (of the overlying unnamed upper part of the Open Door). In the subsurface this same contact shows a drop in resistivity. Recognized only where Dunoir present. Where Dunoir absent, Dry Creek merges with Gros Ventre shale. Has an APHELASPIS fauna in lower 11 ft near Boulder in SW1/4 sec 20, T32N, R107W, Sublette Co, WY in the Greater Green River basin; elsewhere has a basal Franconian ELVINIA zone fauna. These zones are representative Upper Cambrian zones. Represents a new transgression. Cross sections. Identified in logs in Fremont and Natrona Co, WY in the Wind River basin.
Summary of Citation: Dry Creek

Publication:
Richards, P.W., 1957, Geology of the area east and southeast of
   Livingston, Park County, Montana, IN Contributions to general
   geology, 1955: U.S. Geological Survey Bulletin, 1021-L, p.
   L385-L438
Usage in Publication:
Dry Creek shale*

Modifications: Geologic Province: Dominant Lithology:
 Not used
   

Summary:
Not used in report area because of inconsistencies in use of name. Replaced by Snowy Range formation in Livingston area, Park Co, MT, Montana folded belt province, and Sweet Grass Co, MT on Central Montana uplift.
Summary of Citation: Dry Creek

Publication:
Grant, R.E., 1965, Faunas and stratigraphy of the Snowy Range
   Formation (Upper Cambrian) in southwestern Montana and
   northwestern Wyoming: Geological Society of America Memoir,
   96, 171 p.
Usage in Publication:
Dry Creek Member

Modifications: Geologic Province: Dominant Lithology:
 Overview
Age modified
 Montana folded belt province
Central Montana uplift
Bighorn basin
Yellowstone province
 

Summary:
Snowy Range Formation measured at 24 locations in Horseshoe Hills and Bridger Mountains, MT, and at 8 locations elsewhere in MT and WY near Yellowstone National Park between Missouri River and Clarks Fork of Yellowstone River, all within Gallatin, Park, and Carbon Cos, MT and Park Co, WY in Montana folded belt province, Central Montana uplift, Bighorn basin, and Yellowstone province. Snowy Range divided into, in ascending order: Dry Creek, Sage, and Grove Creek Members. Dry Creek is present at all measured sections except at Mount Ellis where it is faulted out. Thickness in Horseshoe Hills ranges from 30-95 ft, averaging 55 ft; in Bridger Mountains, it ranges from 45-105 ft, averaging 65 ft; between Bridger Mountains and Yellowstone, it ranges from 15-30 ft; at Mill Creek, it is 105 ft thick; and east of Yellowstone, it is a relatively constant 50 ft. Overlies Pilgrim Formation with sharp contact. Petrographic descriptions; fossil list and descriptions; cross sections showing trilobite zones. Dresbachian age (early Late Cambrian) fauna of APHELASPIS Zone found in lower part of member at three localities: Bill Smith Creek and Bighorn Lake in Bridger Mountains, MT, and at Fox Creek in Park Co, WY. Dresbachian and Franconian age (early and middle Late Cambrian).
Summary of Citation: Dry Creek

Publication:
Ruppel, E.T., 1972, Geology of pre-Tertiary rocks in the northern
   part of Yellowstone National Park, Wyoming, with a section
   on Tertiary laccoliths, sills, and stocks in and near the
   Gallatin Range, Yellowstone National Park, IN Geology of
   Yellowstone National Park: U.S. Geological Survey Professional
   Paper, 729-A, p. A1-A66
Usage in Publication:
Dry Creek Shale Member*

Modifications: Geologic Province: Dominant Lithology:
 Overview
Reference
 Yellowstone province
Montana folded belt province
 

Summary:
Dry Creek Shale (lowermost), Sage Limestone, and Grove Creek (uppermost) Members mapped undivided as Snowy Range Formation in northern part of Yellowstone National Park, Park Co, WY, Yellowstone province, and Park Co, MT, Montana folded belt province. Dry Creek is about 40 ft thick in Gallatin Range and 50 ft thick on the Buffalo Plateau. Stratigraphic chart. Reference section for Snowy Range designated at Three Rivers Peak, at head of Gallatin River, in Gallatin Range. Conformably overlies Pilgrim Limestone. Late Cambrian age.