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

Geologic units in Eagle county, Colorado

[Additional scientific data in this geographic area]

Middle Tertiary intrusive rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers 0.1 % of this area

Intermediate to felsic compositions

Lithology: plutonic rock (phanerit

Weber Sandstone and Maroon Fm (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian Permian) at surface, covers 4 % of this area

Lithology: sandstone; siltstone; conglomerate

Chinle And State Bridge Fms (Phanerozoic | Paleozoic Mesozoic | Permian Triassic) at surface, covers 2 % of this area

Red siltstone and sandstone

Lithology: siltstone; sandstone

Leadville, Gilman, Dyer, Parting, and Sawatch Fms in west-central and south-central. Leadville Limestone, Ouray Limestone, Elbert Fm, and Ignacio Quartzite in far southwest (Phanerozoic | Paleozoic | Cambrian Ordovician(?) Silurian(?) Devonian(?) Carboniferous) at surface, covers < 0.1 % of this area

Elbert Fm: shale and sandstone.

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

Minturn and Belden Fms (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian) at surface, covers 0.9 % of this area

Lithology: sandstone; shale; limestone; conglomerate

Dakota Sandstone or Group (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 4 % of this area

Lithology: sandstone

Maroon Fm (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian Permian) at surface, covers 10 % of this area

Arkosic sandstone, siltstone, conglomerate, and local limestone

Lithology: sandstone; siltstone; conglomerate; limestone

Dakota and Morrison Fms (Phanerozoic | Mesozoic | Jurassic Cretaceous) at surface, covers 0.3 % of this area

Lithology: sandstone; mudstone; shale

Basalt flows and associated tuff, breccia, and conglomerate of late-volcanic bimodal suite (Phanerozoic | Cenozoic | Tertiary) at surface, covers 7 % of this area

Includes basalts of Hinsdale Fm in San Juan Mountains - Servilleta Fm in San Luis Valley and many other occurrences

Lithology: basalt; tuff; volcanic breccia (agglomerate); conglomerate

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

Includes Broadway and Louviers Alluviums

Lithology: gravel; alluvium

Pierre Shale, undivided (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 4 % of this area

Lithology: shale

Chinle Fm (Phanerozoic | Mesozoic | Triassic) at surface, covers 1 % of this area

Red siltstone, sandstone, and limestone-pellet conglomerate

Lithology: siltstone; sandstone; conglomerate

Morrison Fm (Phanerozoic | Mesozoic | Jurassic) at surface, covers 0.2 % of this area

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

Lithology: mudstone; sandstone; limestone

Basaltic intrusive rocks related to basalt flows (Phanerozoic | Cenozoic | Tertiary) at surface, covers < 0.1 % of this area

In dikes and plugs

Lithology: basalt

Mancos Shale (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 1 % 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

Sawatch Quartzite (Phanerozoic | Paleozoic | Cambrian) at surface, covers 0.1 % of this area

Locally includes Peerless Fm

Lithology: quartzite; sandstone; dolostone (dolomite)

Basalt flows (Phanerozoic | Cenozoic | Quaternary) at surface, covers < 0.1 % of this area

Lithology: basalt

Ancient alluvium (Phanerozoic | Cenozoic | Tertiary Quaternary) at surface, covers 0.5 % of this area

In isolated patches that may not all be of the same age

Lithology: alluvium

Manitou Limestone and Sawatch Quartzite in Southern Front Range and Wet Mountains. One or more Ordovician Fms (Fremont Limestone, Harding Sandstone, and Manitou Dolomite), Dotsero Fm, Peerless Fm, and Sawatch Quartzite in west-ce (Phanerozoic | Paleozoic | Cambrian Ordovician) at surface, covers 0.6 % of this area

Dotsero Fm: Dolomite, in White River plateau only. Peerless Fm: sandstone and dolomite.

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

Morrison Fm and Entrada Sandstone (Phanerozoic | Mesozoic | Jurassic) at surface, covers 0.8 % of this area

Lithology: mudstone; sandstone

Rhyolitic intrusive rocks and flows of late-volcanic bimodal suite (Phanerozoic | Cenozoic | Tertiary) at surface, covers 0.2 % of this area

Lithology: rhyolite

Glacial drift (Phanerozoic | Cenozoic | Quaternary) at surface, covers 4 % of this area

Includes some unclassified glacial deposits

Lithology: glacial drift

Eagle Valley Fm - evaporitic facies (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian) at surface, covers 12 % of this area

Gypsum, siltstone, and shale; salt present in deep borings. Intertongues with Minturn and Lower Maroon Fms. Diapiric structure in many places

Lithology: siltstone; shale; evaporite

Colorado Group (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 3 % of this area

Consists of Niobrara Formation (Kn) and either Benton Shale or Carlile, Greenhorn, and Graneros Fms (Kcg)

Lithology: shale; limestone

Granitic rocks of 1700-m.y. age group (Proterozoic | Paleoproterozoic) at surface, covers 4 % of this area

Includes Boulder Creek -M.Y. AGE GROUP (AGE 1650-1730 M.Y.)--Includes Boulder Creek, Cross Creek, Denny Creek, Kroenke, Browns Pass, Powderhorn, Pitts Meadow, Bakers Bridge, and Tenmile Granites, Quartz Monzonites, or Granodiorites;

Lithology: granite; granodiorite; quartz monzonite

Biotitic gneiss, schist, and migmatite (Proterozoic | Paleoproterozoic) at surface, covers 9 % of this area

Locally contains minor hornblende gneiss, calc-silicate rock, quartzite, and marble. Derived principally from sedimentary rocks

Lithology: biotite gneiss; schist; migmatite; quartzite; marble

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

Mainly intermediate to felsic compositions; some mafic

Lithology: granitoid

Eagle Valley Fm (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian) at surface, covers 0.9 % of this area

Siltstone, shale, and local gypsum

Lithology: siltstone; shale; evaporite

Older glacial drift (Phanerozoic | Cenozoic | Quaternary) at surface, covers 0.4 % of this area

Lithology: glacial drift

Modern alluvium (Phanerozoic | Cenozoic | Quaternary) at surface, covers 0.1 % of this area

Includes Piney Creek Alluvium and younger deposits

Lithology: alluvium

Leadville Limestone, Gilman Sandstone, Dyer Dolomite, and Parting Fm (Phanerozoic | Paleozoic | Ordovician Silurian(?) Devonian) at surface, covers 0.4 % of this area

Parting Fm: quartzite and shale.

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

State Bridge Fm (Phanerozoic | Paleozoic Mesozoic | Permian Triassic) at surface, covers 5 % of this area

Red and orange siltstone and sandstone

Lithology: siltstone; sandstone

Granitic rocks of 1400-m.y. age group (Proterozoic | Mesoproterozoic) at surface, covers < 0.1 % of this area

Includes Silver Plume, Sherman, Cripple Creek, St. Kevin, Vernal Mesa, Curecanti, Eolus, and Trimble Granites or Quartz Monzonites; also, San Isabel Granite of Boyer (1962) and unnamed granitic rocks

Lithology: granite; granodiorite; quartz monzonite

Felsic and hornblendic gneisses, either separate or interlayered (Proterozoic | Paleoproterozoic) at surface, covers 0.2 % of this area

Includes metabasalt, metatuff, and interbedded metagraywacke; locally contains interlayered biotite gneiss. Derived principally from volcanic rocks

Lithology: felsic gneiss; mafic gneiss; meta-basalt; meta-graywacke

Leadville Limestone, Williams Canyon Limestone , Manitou Limestone, and Sawatch Quartzite (Phanerozoic | Paleozoic | Cambrian Ordovician(?) Silurian(?) Devonian(?) Carboniferous) at surface, covers 1 % of this area

Lithology: limestone; quartzite

Belden Fm (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian) at surface, covers 1 % of this area

Shale, limestone, and sandstone. Includes Kerber Fm in south-central

Lithology: shale; limestone; sandstone

Minturn Fm in west-central and south-central and other units (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian) at surface, covers 10 % of this area

Arkosic sandstone, conglomerate, shale, and limestone. Includes Madera Fm and Sharpsdale Fm of Chronic (1958) in Sangre de Cristo Range and Gothic Fm of Langenheim (1952) in Elk Mountains. Other units of Middle Pennsylvanian age.

Lithology: sandstone; conglomerate; shale; limestone

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

In extreme southwestern Moffat County, includes thin wedge of Carmel Fm (red siltstone and sandstone) beneath Entrada

Lithology: mudstone; sandstone

Browns Park Fm (Phanerozoic | Cenozoic | Tertiary) at surface, covers 1 % of this area

Sandstone and siltstone; west of Park Range

Lithology: sandstone; siltstone

Landslide deposits (Phanerozoic | Cenozoic | Quaternary) at surface, covers 5 % of this area

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

Lithology: landslide; talus; colluvium

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 1 % of this area

Lithology: sandstone; mudstone; limestone

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