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Mineral Resources > Online Spatial Data > Geology > by state > Colorado Geology

Geologic units in Ouray county, Colorado

[Additional scientific data in this geographic area]

Uncompahgre Fm (Proterozoic | Paleoproterozoic Mesoproterozoic) at surface, covers 0.5 % of this area

Quartzite, slate, and phyllite

Lithology: quartzite; slate; phyllite

Middle Tertiary intrusive rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers 0.8 % of this area

Intermediate to felsic compositions

Lithology: plutonic rock (phanerit

Telluride conglomerate of Eocene prevolcanic sedimentary rocks (Te) and Cimarron Ridge Fm (Phanerozoic | Mesozoic Cenozoic | Cretaceous Tertiary) at surface, covers 0.6 % of this area

In northwestern San Juan Mountains. Cimarron Ridge Fm: volcanic breccia and conglomerate.

Lithology: conglomerate; volcanic breccia (agglomer

Intra-ash flow andesitic lavas (Phanerozoic | Cenozoic | Tertiary) at surface, covers 4 % of this area

Lithology: andesite

Ash-flow tuff of main volcanic sequence (Phanerozoic | Cenozoic | Tertiary) at surface, covers 2 % of this area

Includes many named units

Lithology: ash-flow tuff

Pre-ash-flow andesitic lavas, breccias, tuffs, and conglomerates (Phanerozoic | Cenozoic | Tertiary) at surface, covers 20 % of this area

Includes several named units

Lithology: andesite; tuff; volcanic breccia (agglomerate)

Gravels and alluviums (Phanerozoic | Cenozoic | Quaternary) at surface, covers 2 % of this area

Includes Broadway and Louviers Alluviums

Lithology: gravel; alluvium

Morrison Fm (Phanerozoic | Mesozoic | Jurassic) at surface, covers 0.6 % of this area

Variegated claystone, mudstone, sandstone, and local beds of limestone

Lithology: mudstone; sandstone; limestone

Mancos Shale (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 19 % of this area

In northwest and west-central: Intertongues complexly with units of overlying Mesaverde Group or Fm; lower part consists of a calcareous Niobrara equivalent and Frontier Sandstone and Mowry Shale Members; in areas where the Frontie

Lithology: shale; sandstone

Dakota Sandstone and Burro Canyon Fm (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 23 % of this area

Sandstone, shale, and conglomerate. In northwest and west-central: Lower Cretaceous. In southwest: Lower and Upper Cretaceous.

Lithology: sandstone; shale; conglomerate

Hermosa Fm (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian) at surface, covers 0.4 % of this area

Arkosic sandstone, conglomerate, shale, and limestone; gypsum and salt in Paradox Member present in salt anticlines near Utah border

Lithology: sandstone; conglomerate; shale; limestone; evaporite

Glacial drift (Phanerozoic | Cenozoic | Quaternary) at surface, covers 1.0 % of this area

Includes some unclassified glacial deposits

Lithology: glacial drift

Eocene prevolcanic sedimentary rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers 0.5 % of this area

South-central: Arkosic sand and bouldery gravel of Echo Park Alluvium. Southwest: includes Telluride Conglomerate and Blanco Basin Fm (arkosic mudstone, sandstone, and conglomerate)

Lithology: sandstone; conglomerate; mudstone

Laramide intrusive rocks (Phanerozoic | Mesozoic Cenozoic | Cretaceous Tertiary) at surface, covers 1 % of this area

Mainly intermediate to felsic compositions; some mafic

Lithology: granitoid

Dolores Fm and Cutler Fm (Phanerozoic | Paleozoic Mesozoic | Permian Triassic) at surface, covers 1 % of this area

Red siltstone, sandstone, and conglomerate

Lithology: siltstone; sandstone; conglomerate

Older glacial drift (Phanerozoic | Cenozoic | Quaternary) at surface, covers 0.6 % of this area

Lithology: glacial drift

Leadville Limestone, Gilman Sandstone, Dyer Dolomite, and Parting Fm (Phanerozoic | Paleozoic | Ordovician Silurian(?) Devonian) at surface, covers 0.3 % of this area

Parting Fm: quartzite and shale.

Lithology: limestone; sandstone; dolostone (dolomite); shale; quartzite

Modern alluvium (Phanerozoic | Cenozoic | Quaternary) at surface, covers 2 % of this area

Includes Piney Creek Alluvium and younger deposits

Lithology: alluvium

Morrison Fm, Summerville Fm, and Entrada Sandstone (Phanerozoic | Mesozoic | Jurassic) at surface, covers 2 % of this area

Summerville Fm: Shale and siltstone

Lithology: mudstone; sandstone

Dakota, Purgatoire, Morrison, Ralston Creek, and Entrada Fms in southeast. Dakota, Morrison, and Entrada Fms in central mountains. Dakota, Burro Canyon, Morrison, Wanakah, and Entrada Fms in Gunnison River area. Dakota, Morriso (Phanerozoic | Mesozoic | Jurassic Cretaceous) at surface, covers 3 % of this area

Lithology: sandstone; mudstone; limestone

Landslide deposits (Phanerozoic | Cenozoic | Quaternary) at surface, covers 14 % of this area

Locally includes talus, rock-glacier, and thick colluvial deposits

Lithology: landslide; talus; colluvium

Older gravels and alluviums (Phanerozoic | Cenozoic | Quaternary) at surface, covers 0.1 % of this area

Includes Slocum, Verdos, Rocky Flats, and Nussbaum Alluviums in east, and Florida, Bridgetimber, and Bayfield Gravels in southwest

Lithology: gravel; alluvium

Morrison, Wanakah, and Entrada Fms (Phanerozoic | Mesozoic | Jurassic) at surface, covers 1 % of this area

Lithology: mudstone; sandstone; limestone