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

Geologic units in Clear Creek county, Colorado

[Additional scientific data in this geographic area]

Glacial drift (Phanerozoic | Cenozoic | Quaternary) at surface, covers 9 % of this area

Includes some unclassified glacial deposits

Lithology: glacial drift

Middle Tertiary intrusive rocks (Phanerozoic | Cenozoic | Tertiary) at surface, covers 0.2 % of this area

Intermediate to felsic compositions

Lithology: plutonic rock (phanerit

Granitic rocks of 1400-m.y. age group (Proterozoic | Mesoproterozoic) at surface, covers 25 % 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 10 % 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

Rocks of Pikes Peak Batholith (1000-m.y. age group) (Proterozoic | Mesoproterozoic) at surface, covers 0.3 % of this area

Includes Pikes Peak, Mount Rosa, Windy Point, and Redskin Granites and unnamed rocks

Lithology: granite; granodiorite; quartz monzonite

Landslide deposits (Phanerozoic | Cenozoic | Quaternary) at surface, covers 0.2 % of this area

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

Lithology: landslide; talus; colluvium

Biotitic gneiss, schist, and migmatite (Proterozoic | Paleoproterozoic) at surface, covers 33 % 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

Granitic rocks of 1700-m.y. age group (Proterozoic | Paleoproterozoic) at surface, covers 20 % 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

Bouldery gravel on old erosion surfaces in Front Range and Never Summer Mountains (Phanerozoic | Cenozoic | Tertiary) at surface, covers 0.2 % of this area

Lithology: gravel