State | Texas |
---|---|
Name | Dockum Group, undivided |
Geologic age | Late Triassic |
Lithologic constituents |
Major
Sedimentary > Clastic > Mudstone > Shale (Bed)
Minor
Sedimentary > Clastic > Mixed-clastic > Sandstone-mudstone (Bed)
Incidental
Sedimentary > Carbonate > Limestone (Bed)
Sedimentary > Clastic > Conglomerate (Bed)
|
Comments | Well exposed near town of Dockum, Dickens Co., TX. Continental redbed sequence deposited unconformably on Upper Permian (Quartermaster Fm in Tucumcari Sheet (1983). Shale, sandst., siltst., ls., and gravel; mostly shale, miceous, thinbedded, variegated; thickness up to 300 ft. or 400 ft +_ on Lubbock Sheet (1983). correlative with Chinle Fm (above) and Santa Rosa Ss (below). |
Stratigraphic units | basal unit Santa Rosa Formation (Sandstone), ascending units are Tecovas Formation, Trujillo Formation, Chinle Formation |
References | Bureau of Economic Geology, 1983, Tucumcari Sheet, Geologic Atlas of Texas, Bureau of Economic Geology, University of Texas at Austin, scale 1:250,000.Finch, W.I., 1988, Description of the principal reference for the Santa Rosa Formation, Chapter A, in Principal reference section for the Santa Rosa Formation. . ., Guadalupe County, New Mexico: U.S. Geological Survey Bulletin 1804, p. 1-10.https://pubs.er.usgs.gov/publication/b1804 Bureau of Economic Geology, 1983, Lubbock Sheet, Geologic Atlas of Texas: University of Texas at Austin, Bureau of Economic Geology, scale 1:250,000.Bureau of Economic Geology, 1976, Hobbs Sheet, Geologic Atlas of Texas: University of Texas at Austin, Bureau of Economic Geology, scale 1:250,000.Bureau of Economic Geology, 1992, Geologic Map of Texas: University of Texas at Austin, Virgil E. Barnes, project supervisor, Hartmann, B.M. and Scranton, D.F., cartography, scale 1:500,000.Bureau of Economic Geology, 1992, Geologic Map of Texas: University of Texas at Austin, Virgil E. Barnes, project supervisor, Hartmann, B.M. and Scranton, D.F., cartography, scale 1:500,000. |
NGMDB product | |
Counties | Andrews - Armstrong - Borden - Briscoe - Coke - Crane - Crosby - Dawson - Deaf Smith - Dickens - Ector - Fisher - Floyd - Garza - Howard - Kent - Loving - Lubbock - Lynn - Martin - Midland - Mitchell - Motley - Nolan - Randall - Reeves - Scurry - Sterling - Stonewall - Upton - Ward - Winkler |