Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Tide and storm-dominated sand ridges on a muddy shelf: Cottage Grove sandstone (upper Pennsylvanian), northwestern Oklahoma

Journal Article · · AAPG (Am. Assoc. Pet. Geol.) Bull.; (United States)
OSTI ID:6025718
Approximately 20 sandstone ridges of the Cottage Grove Sandstone, encased in shale and mudstone, can be identified from subsurface control within a 504 mi/sup 2/ (1305 km/sup 2/) study area in northwestern Oklahoma. The sandstone ridges range in width from 0.6 to 2.5 mi (1 to 4 km) and in length from 2.5 to more than 18.6 mi (4 to more than 30 km). Maximum sandstone thickness is about 100 ft (30 m). The sandstone ridges trend generally northeast-southwest, oblique to present structural strike. The sandstones show an overall fining-upward trend unlike many reported shelf deposits. A general vertical facies sequence from an axial core on a sand ridge consists of (1) mudstone (basal), (2) wavy bedded sandstone/shale, (3) alternating massive sandstone containing symmetrical oscillation ripples and flaser-bedded and horizontally bedded sandstone with herringbone cross-stratification, and (4) wavy bedded sandstone/shale, which grades into the mudstone facies above. A fossiliferous packstone-grainstone facies also occurs as thin sheets in some sandstone ridges as well as interridge areas. The Cottage Grove Sandstone ridges were deposited in a shelf environment. Inferred depositional processes include reworking by tidal surge and ebb, winnowing of ridge crests by wave action during storms, and, perhaps, episodic delivery of sediment to the shelf by storm-induced currents. The fining-upward trend in the sandstone bodies suggests deposition in a transgressive setting. The characteristics and inferred processes of the Cottage Grove Sandstone bodies are consistent with an origin similar to modern shoreface-detached sand ridges. 13 figures.
Research Organization:
Univ. of Oklahoma, Norman (USA)
OSTI ID:
6025718
Journal Information:
AAPG (Am. Assoc. Pet. Geol.) Bull.; (United States), Journal Name: AAPG (Am. Assoc. Pet. Geol.) Bull.; (United States) Vol. 72:10; ISSN AABUD
Country of Publication:
United States
Language:
English