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

Geologic units in Hinsdale county, Colorado

[Additional scientific data in this geographic area]

Morrison, Wanakah, and Entrada Fms (Phanerozoic | Mesozoic | Jurassic) at surface, covers 3 % of this area

Lithology: mudstone; sandstone; limestone

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

Cutler Fm (Phanerozoic | Paleozoic | Permian) at surface, covers 0.1 % of this area

Arkosic sandstone, siltstone, and conglomerate

Lithology: sandstone; siltstone; conglomerate

Intra-ash flow quartz latitic lavas (Phanerozoic | Cenozoic | Tertiary) at surface, covers 5 % of this area

Lithology: quartz latite

Felsic and hornblendic gneisses, either separate or interlayered (Proterozoic | Paleoproterozoic) at surface, covers 0.8 % 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

Granitic rocks of 1400-m.y. age group (Proterozoic | Mesoproterozoic) at surface, covers 7 % 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

Quartzite, conglomerate, and interlayered mica schist (Proterozoic | Paleoproterozoic) at surface, covers 1 % of this area

Quartzite, conglomerate, and interlayered mica schist

Lithology: quartzite; conglomerate; mica schist

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

Pictured Cliffs Sandstone and Lewis Shale (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 0.3 % of this area

Lithology: sandstone; shale

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

Includes Piney Creek Alluvium and younger deposits

Lithology: alluvium

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

Lithology: glacial drift

Mesaverde Fm, undivided (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 0.3 % of this area

In northwest and west-central: Major coal beds in lower part; Rollins Sandstone Member at base in Delta, Gunnison, and Pitkin Counties. In southwest: sandstone and shale.

Lithology: sandstone; shale; coal

Eocene prevolcanic sedimentary rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers < 0.1 % 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

Rico and Hermosa Fms (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian) at surface, covers 1 % of this area

Arkosic sandstone, conglomerate, shale, and limestone. Includes at base in some areas siltstone and shale of Molas Fm or Larsen Quartzite

Lithology: sandstone; conglomerate; shale; limestone; mudstone

Glacial drift (Phanerozoic | Cenozoic | Quaternary) at surface, covers 7 % of this area

Includes some unclassified glacial deposits

Lithology: glacial drift

Rhyolitic intrusive rocks and flows of late-volcanic bimodal suite (Phanerozoic | Cenozoic | Tertiary) at surface, covers 1 % of this area

Lithology: rhyolite

Mancos Shale (Phanerozoic | Mesozoic | Cretaceous) at surface, covers 2 % 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 1 % of this area

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

Lithology: sandstone; shale; conglomerate

Ash-flow tuff of late-volcanic bimodal suite (Phanerozoic | Cenozoic | Tertiary) at surface, covers 5 % of this area

Lithology: ash-flow tuff

Pre-ash-flow andesitic lavas, breccias, tuffs, and conglomerates (Phanerozoic | Cenozoic | Tertiary) at surface, covers 13 % of this area

Includes several named units

Lithology: andesite; tuff; volcanic breccia (agglomerate)

Gravels and alluviums (Phanerozoic | Cenozoic | Quaternary) at surface, covers 0.9 % of this area

Includes Broadway and Louviers Alluviums

Lithology: gravel; alluvium

Intra-ash flow andesitic lavas (Phanerozoic | Cenozoic | Tertiary) at surface, covers 12 % of this area

Lithology: andesite

Basalt flows and associated tuff, breccia, and conglomerate of late-volcanic bimodal suite (Phanerozoic | Cenozoic | Tertiary) at surface, covers 5 % 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

Ash-flow tuff of main volcanic sequence (Phanerozoic | Cenozoic | Tertiary) at surface, covers 26 % of this area

Includes many named units

Lithology: ash-flow tuff

Dolores Fm (Phanerozoic | Mesozoic | Triassic) at surface, covers 0.3 % of this area

Red siltstone, shale, sandstone, and limestone-pellet conglomerate

Lithology: siltstone; shale; sandstone; conglomerate

Alkalic and mafic rocks in small plutons, and diabase and gabbro dikes (Proterozoic | Mesoproterozoic) at surface, covers 0.1 % of this area

Alkalic and mafic rocks in small plutons, and diabase and gabbro dikes

Lithology: granitoid; diabase; gabbro

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 0.2 % of this area

Elbert Fm: shale and sandstone.

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

Uncompahgre Fm (Proterozoic | Paleoproterozoic Mesoproterozoic) at surface, covers 1 % of this area

Quartzite, slate, and phyllite

Lithology: quartzite; slate; phyllite

Middle Tertiary intrusive rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers 0.5 % of this area

Intermediate to felsic compositions

Lithology: plutonic rock (phanerit