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

Geologic units in Costilla county, Colorado

[Additional scientific data in this geographic area]

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 < 0.1 % of this area

Lithology: sandstone; mudstone; limestone

South Park Fm (Phanerozoic | Cenozoic | Tertiary) at surface, covers 0.3 % of this area

Arkosic sandstone and shale, volcaniclastic conglomerate, and andesite flows and breccia

Lithology: sandstone; shale; conglomerate; andesite; volcanic breccia (agglo

Quartzite, conglomerate, and interlayered mica schist (Proterozoic | Paleoproterozoic) at surface, covers 0.2 % of this area

Quartzite, conglomerate, and interlayered mica schist

Lithology: quartzite; conglomerate; mica schist

Granitic rocks of 1400-m.y. age group (Proterozoic | Mesoproterozoic) at surface, covers 2 % 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

Minturn Fm in west-central and south-central and other units (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian) at surface, covers 5 % 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

Belden Fm (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian) at surface, covers 0.3 % of this area

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

Lithology: shale; limestone; sandstone

Felsic and hornblendic gneisses, either separate or interlayered (Proterozoic | Paleoproterozoic) at surface, covers 14 % 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

Santa Fe Fm (Phanerozoic | Cenozoic | Tertiary) at surface, covers 20 % of this area

Siltstone, sandstone, and conglomerate

Lithology: siltstone; sandstone; conglomerate

Sangre de Cristo Fm (Phanerozoic | Paleozoic | Carboniferous Pennsylvanian Permian) at surface, covers 3 % of this area

Arkosic conglomerate, sandstone, and siltstone

Lithology: conglomerate; sandstone; siltstone

Mafic rocks of 1700-m.y. age group (Proterozoic | Paleoproterozoic) at surface, covers 0.3 % of this area

Gabbro and mafic diorite and monzonite

Lithology: gabbro; diorite; monzonite

Biotitic gneiss, schist, and migmatite (Proterozoic | Paleoproterozoic) at surface, covers 1 % 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

Granitic rocks of 1700-m.y. age group (Proterozoic | Paleoproterozoic) at surface, covers 3 % 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

Glacial drift (Phanerozoic | Cenozoic | Quaternary) at surface, covers 1 % of this area

Includes some unclassified glacial deposits

Lithology: glacial drift

Basalt flows (Phanerozoic | Cenozoic | Quaternary) at surface, covers 0.3 % of this area

Lithology: basalt

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

In dikes and plugs

Lithology: basalt

Pre-ash-flow andesitic lavas, breccias, tuffs, and conglomerates (Phanerozoic | Cenozoic | Tertiary) at surface, covers 5 % of this area

Includes several named units

Lithology: andesite; tuff; volcanic breccia (agglomerate)

Gravels and alluviums (Phanerozoic | Cenozoic | Quaternary) at surface, covers 26 % of this area

Includes Broadway and Louviers Alluviums

Lithology: gravel; alluvium

Unclassified surficial deposits and underlying Alamosa Fm in San Luis Valley (Phanerozoic | Cenozoic | Tertiary Quaternary) at surface, covers 10 % of this area

Alamosa Fm: gravel, sand, silt

Lithology: alluvium

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

Intra-ash flow andesitic lavas (Phanerozoic | Cenozoic | Tertiary) at surface, covers 1 % of this area

Lithology: andesite

Pierre Shale (Kp), Niobrara (Kn), and Carlile, Greenhorn, and Graneros (Kcg) Fms, undivided (Phanerozoic | Mesozoic | Cretaceous) at surface, covers < 0.1 % of this area

Lithology: shale; limestone

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

Intermediate to felsic compositions

Lithology: plutonic rock (phanerit