Stratigraphic Units of the Colorado Plateau, by Age
This list consists of named stratigraphic units reported in USGS publications arranged by geologic age. Some units that span a geologic time boundaries are noted. Some of the units are exposed only along the margins of the Colorado Plateau region. Other units are only interpreted to be in the region from drilling and other subsurface data. Note that units with each time division are not differentiated - they are only listed alphabetically. No attempt is presented here to correlate named units from one location to another - this kind of information is presented in many of the published reports listed as bibliographic references on individual rock unit pages.Cenozoic Era
Quaternary Period
Quaternary-age rocks of the Colorado Plateau
Tertiary Period
Pliocene Epoch
Bidahochi Formation (spans Miocene)
Hualapai Member (Muddy Creek Fm.)
Miocene Epoch
Bitter Ridge Member (Horse Spring Fm.)
Horse Spring Formation
Lovell Wash Member (Horse Spring Fm.)
Muddy Creek Formation (spans Pliocene)
Osiris Tuff
Rainbow Gardens Member (Horse Spring Fm.)
Red Sandstone
Rocks of the Grand Wash Trough
Thumb Member (Horse Spring Fm.)
Oligocene Epoch
Boat Mesa Formation
Browns Park Formation
Mount Dutton Formation (spans Miocene)
Eocene Epoch
Bridger Formation
Claron Formation (spans Paleocene? to Oligocene)
Duchesne River Formation (spans Paleocene? to Oligocene)
Green River Formation (spans Paleocene)
Laney Member (Green River Fm.)
Pink Hollow Formation
Tipton Shale Member (Green River Fm.)
Uinta Formation
Wasatch Group (spans Paleocene)
Wilkins Peak Member (Green River Fm.)
Paleocen Epoch
Canaan Peak Formation
Colton Formation (spans Eocene)
Flagstaff Limestone (spans Eocene)
North Horn Formation (spans Cretaceous)
Mesozoic Era
Cretaceous Period
Barker Dome Tongue (Cliffhouse Ss.)
Baxter Formation
Blair Formation
Blue Gate Member (Mancos Shale)
Buck Tongue (Mancos Shale)
Burrow Canyon Formation
Castlegate Sandstone
Cedar Mountain Formation
Cliffhouse Sandstone Member (Mesaverde Fm.)
Dakota Sandstone
Drip Tank Member (Straight Cliffs Fm.)
Ericson Sandstone (Mesaverde Group)
Ferron Sandstone Member (Mancos Shale)
Fort Union Formation
Frontier Formation
John Henry Member (Straight Cliffs Fm.)
Kaiparowitz Formation
Lewis Shale
Mancos Shale
Masok Member (Mancos Shale)
Menefee Formation (Mesaverde Group)
Mesaverde Formation (or Group)
Mowry Shale
Muley Canyon Member (Mancos Shale)
Pictured Cliffs Sandstone
Point Lookout Sandstone (Mesaverde)
Rock Springs Formation
Sego Sandstone (Mesaverde)
Smoky Hollow Member (Straight Cliffs Fm.)
Straight Cliffs Formation
Tibbet Canyon Member (Straight Cliffs Fm.)
Tropic Shale
Tunuck Member (Mancos Shale)
Wahweap Formation
Jurassic Period
Aztec Sandstone (spans into Triassic)
Brushy Basin Member (Morrison Fm.)
Cannonville Member (Entrada Formation)
Carmel Formation
Chinle Formation
Co-op Canyon Member (Carmel Fm.)
Crystal Creek Member (Carmel Fm.)
Curtis Formation
Dinosaur Canyon Member (Moenave Fm.)
Entrada Sandstone
Escalante Member (Entrada Fm.)
Glen Canyon Group
Gunsight Butte Member (Entrada Fm.)
Judd Hollow Member (Carmel Fm.)
Kayenta Formation (spans Triassic?)
Lamb Point Tongue (Navajo Ss.) (spans Triassic?)
Moenave Formation (spans Triassic?)
Morrison Formation
Navajo Sandstone (spans Triassic)
Nugget Formation (spans Triassic?)
Page Sandstone
Paria River Member (Carmel Fm.)
Romana Sandstone
Salt Wash Member (Morrison Fm.)
San Rafael Group
Springdale Sandstone Member (Moenave Fm.)
Sinawava Member (Temple Cap Fm.)
Stump Formation
Summerville Formation
Temple Cap Formation
Tenney Canyon Member (Kayenta Fm.) (spans Triassic?)
Tiddwell Member (Morrison Fm.)
Wanakah Formation
White Throne Member (Temple Cap Fm.)
Whitmore Point Member (Moenave Fm.)
Wingate Sandstone
Winsor Member (Carmel Fm.)
Triassic Period
Black Dragon Member (Moenkopi Fm.)
Church Rock Member (Chinle Fm.)
Dinwoody Formation
Holbrook Member (Moenkopi Fm.)
Hoskinnini Member (Moenkopi Fm.)
Moenkopi Formation
Monitor Butte Member (Chinle Fm.)
Moody Canyon Member (Moenkopi Fm.)
Moqui Member (Moenkopi Fm.)
Mossback Member (Chile Fm.)
Owl Rock Member (Chinle Fm.)
Petrified Forest Member (Chinle Fm.)
Rock Canyon Member (Moenkopi Fm.)
Shinarump Conglomerate (Chinle Fm.)
Shnabkaib Member (Moenkopi Fm.)
Sinbad Limestone Member (Moenkopi Fm.)
Temple Mountain Member (Chinle Fm.)
Timpoweap Member (Moenkopi Fm.)
Torrey Member (Moenkopi Fm.)
Virgin Limestone Member (Moenkopi Fm.)
Wupatki Member (Moenkopi Fm.)
Paleozoic Era
Permian Period
Black Box Formation
Brady Canyon Member (Toroweap Fm.)
Cedar Mesa Sandstone
Coconino Sandstone
Cutler Group (Formation)
De Chelly Sandstone
Esplande Formation
Fossil Mountain Member (Kaibab Ls.)
Halgaito Member (Cutler Fm.)
Harrisburg Member (Kaibab Ls.)
Hermit Shale
Kaibab Limestone
Organ Rock Formation
Pakoon Formation
Park City Formation
Phosphoria Formation
Queantoweap Sandstone
Seligman Member (Toroweap Fm.)
Toroweap Formation
White Rim Sandstone
Wood Ranch Member (Toroweap Fm.)
Pennyslvanian Period
Callville Formation
Elephant Canyon Formation (spans Permian)
Hermosa Group
Honaker Trail Formation
Manakacha Formation
Morgan Formation
Paradox Formation
Pinkerton Trail Formation
Round Valley Limestone
Supai Group (spans Mississippian? to Permian)
Watahomigi Formation (spans Mississippian?)
Weber Sandstone (spans Permian)
Wescogame Formation (Supai Group)
Mississippian Period
Doughnut Shale
Humbug Formation
Madison Formation
Monte Cristo Limestone
Redwall Limestone
Surprise Canyon Formation
Devonian Period
Muddy Peak Limestone
Sultan Limestone (spans Mississippian)
Temple Butte Formation
Silurian Period
Rocks of this age are not known on the Colorado Plateau.
Ordovician Period
Rocks of this age are not known on the Colorado Plateau.
Cambrian Period
Bonanza King Formation
Bright Angel Shale
Chisholm Shale
Dunderberg Shale
Frenchman Mountain Dolomite
Lodore Formation
Lyndon Limestone
Muav Limestone
Nopah Dolomite
Pioche Shale
Tapeats Sandstone
Tonto Group
Precambrian Era
Precambrian-age rocks of the Colorado Plateau
Bass Formation
Cardenas Lava
Chuar Group
Dox Sandstone
Galeros Formation
Grand Canyon Supergroup
Hakatai Shale
Kwagunt Formation
Nankoweap Formation
Owiyukuts Complex
Red Creek Quartzite
Shinumo Quartzite
Sixtymile Formation
Uinta Mountain Group
Vishnu Basement Rocks
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