Brushy Basin Member of Morrison Formation

Usage of Geologic Unit Name:
Brushy Basin Member of Morrison Formation (AZ*,CO*,NM*,UT*)
Jurassic, Late*
Cretaceous, Early (local)
Neocomian (local)
Barremian (local)
Aptian (local)
Albian (local)
Geologic Province:
Paradox basin*
Black Mesa basin*
San Juan basin*
Areal Extent:

Type Locality:
Not designated. Well exposed in Brushy Basin, San Juan Co., UT (Gregory, 1938).

Jackpile Bed (NM).

Unit Name History:
Named as a member of Morrison Formation (Gregory, 1938). Overview (Freeman and Hilpert, 1957). Revised (Ekren and Houser, 1959). Isotopic dating (Marvin and Dobson, 1979). Revised (Owen and others, 1984). Age modified locally; Isotopic dating (Kowallis and Heaton, 1987). Revised (Aubrey, 1988; Peterson, 1988). Isotopic dating (Kowallis and others, 1991). Areal limits;


Gregory, H.E., 1938, The San Juan country; a geographic and geologic reconnaissance of southeastern Utah, with contributions by M.R. Thorpe and H.D. Miser: U.S. Geological Survey
Professional Paper, 188, 123 p.

Freeman, V.L. and Hilpert, L.S., 1957, Stratigraphy of the Morrison formation in part of northwestern New Mexico, IN Contributions to the geology of uranium, 1955: U.S. Geological
Survey Bulletin, 1030-J, p. J309-J334.

Ekren, E.B. and Houser, F.N., 1959, Relations of Lower Cretaceous and Upper Jurassic rocks, Four Corners area, Colorado: American Association of Petroleum Geologists Bulletin, v. 43, no. 1, p. 190-201.

Marvin, R.F. and Dobson, S.W., 1979, Radiometric ages; compilation "B", U.S. Geological Survey: Isochron/West, no. 26, p. 3-32.

Owen, D.E., Walters, L.J., Jr. and Beck, R.G., 1984, The Jackpile Sandstone Member of the Morrison Formation in west-central New Mexico; a formal definition: New Mexico Geology, v. 6, no. 3, p. 45-52.

Kowallis, B.J. and Heaton, J.S., 1987, Fission-track dating of bentonites and bentonitic mudstones from the Morrison Formation in central Utah: Geological Society of America, Geology, v. 15, no. 12, p. 1138-1142.

Aubrey, W.M., 1988, The Encinal Canyon Member, a new member of the Upper Cretaceous Dakota Sandstone in the southern and eastern San Juan basin, New Mexico, IN Revisions to stratigraphic nomenclature of Jurassic and Cretaceous rocks of the Colorado Plateau: U.S. Geological Survey Bulletin, 1633-C, p. C57-C69.

Peterson, Fred, 1988, Stratigraphy and nomenclature of Middle and Upper Jurassic rocks, western Colorado Plateau, Utah and Arizona, IN Revisions to stratigraphic nomenclature of Jurassic and Cretaceous rocks of the Colorado Plateau: U.S. Geological Survey Bulletin, 1633-B, p. B13-56.

Kowallis, B.J., Christiansen, E.H. and Deino, A.L., 1991, Age of the Brushy Basin Member of the Morrison Formation, Colorado Plateau, western USA: Cretaceous Research, v. 12, p. 483-493.

Turner-Peterson, C.E., in press, Sedimentology of the Westwater Canyon and Brushy Basin Members, Upper Jurassic Morrison Formation, Colorado Plateau, and relationship to uranium mineralization: U.S. Geological Survey Professional Paper, __

Galli, Kenneth Gerard, 2003, Sedimentology and petrology of the Brushy Basin Member, Morrison Formation (Late Jurassic), western Colorado: University of Massachusetts, Amherst, MA, PhD dissertation.

Engelmann, George F., and Fiorillo, A. R., 2000, The taphonomy and paleoecology of the Upper Jurassic Morrison Formation determined from a field study of fossil localities: GeoResearch Forum, v. 6, p. 533-540.

Morgan, Susan K., Lindsay, Bradford W., and Williams, Anthony P., 2000, Geology of Escalante State Park, Utah. In, Geology of Utah's parks and monuments: Sprinkel, Douglas A., Chidsey, Thomas C., Jr., and Anderson, Paul B., editors, Utah Geological Association Publication, vol.28, pp.410-420.

Heckert, Andrew B., Lucas, Spencer G., Zeigler, Kate E., Peterson, Ronald E., Peterson, Rodney E., D'Andrea, N V Dan, 2000, Stratigraphy, taphonomy, and new discoveries from the Upper Jurassic (Morrison Formation, Brushy Basin Member) Peterson Quarry, central New Mexico: New Mexico Museum of Natural History and Science, Bulletin, v. 17, p. 51-59.

Bilbey, Sue Ann, 1999, Taphonomy of the Cleveland-Lloyd Dinosaur Quarry in the Morrison
Formation, central Utah., a lethal spring-fed pond: In, Vertebrate paleontology in Utah, Gillette, David D., ed., Utah Geological Survey, Miscellaneous Publication, v. 99-1, p. 121-133.

Anderson, Orin J., and Lucas, Spencer G., 1995, Major redefinition of Morrison Formation and upper San Rafael Group on the Colorado Plateau: AAPG Bulletin, v. 79, no. 6, p. 914.

Bazard, David R., Butler, Robert F., 1994, Paleomagnetism of the Brushy Basin Member of the Morrison Formation., implications for Jurassic apparent polar wander: Journal of Geophysical Research, B, Solid Earth and Planets, v. 99, no. 4, p. 6695-6710.

Masura, Julie Elizabeth, 1998, Stratigraphy and sedimentology of the Upper Jurassic Brushy Basin Member of the Morrison Formation near Tidwell Wash, Emery County, Utah, and description of the depositional environment: Washington State University, Pullman, WA, masters thesis.

Newell, Dennis Lowell, 1997, Geology of the Brushy Basin Member of the Morrison Formation,
Fruita Paleontological Resource Area, Colorado: Colorado State University, Fort Collins, CO, masters thesis.

Anderson, Orin J., and Lucas, Spencer G., 1997, Lake T'oo'dichi' and the Brushy Basin of the Morrison Formation. In, Mesozoic geology and paleontology of the Four Corners region: Anderson, Orin J., Kues, Barry S., and Lucas, Spencer G., editors, New Mexico Geological Society Guidebook, v. 48, p. 2.

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Last modified: 1/7/2011