Includes Pikes Peak, Mount Rosa, Windy Point, and Redskin Granites and unnamed rocks
Locally contains minor hornblende gneiss, calc-silicate rock, quartzite, and marble. Derived principally from sedimentary rocks
Sandstone, mudstone, claystone, and conglomerate; Denver is characterized by andesitic materials
Includes metabasalt, metatuff, and interbedded metagraywacke; locally contains interlayered biotite gneiss. Derived principally from volcanic rocks
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
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; also, unnamed granitic rocks
Includes Slocum, Verdos, Rocky Flats, and Nussbaum Alluviums in east, and Florida, Bridgetimber, and Bayfield Gravels in southwest
Laramie Fm and Fox Hills Sandstone
Includes Piney Creek Alluvium and younger deposits
Arkosic sandstone and conglomerate
Includes Broadway and Louviers Alluviums
Quartzite, conglomerate, and interlayered mica schist
Pierre Shale--Upper unit
Dakota Group and Morrison And Ralston Creek Fms at mountain front between Boulder and Colorado Springs. Dakota, Purgatoire, Morrison, and Ralston Creek Fms in Canon City area
Consists of Niobrara Formation (Kn) and either Benton Shale or Carlile, Greenhorn, and Graneros Fms (Kcg)
Lykins Fm and Lyons Sandstone
Sharon Springs Member (organic-rich shale and numerous bentonite beds) in lower part
Red siltstone, sandstone, and conglomerate
In Boulder-Fort Collins area, contains Richard, Larimer, Rocky Ridge, Terry, and Hygiene Sandstone Members; elsewhere shale between zones of Baculites reesidei and B. scotti
Basaltic flows in Denver Fm near Golden
Arkosic sandstone, shale, mudstone, conglomerate, and local coal beds
Bouldery gravel on old erosion surfaces in Front Range and Never Summer Mountains
Pierre Shale (Kp), Niobrara (Kn), and Carlile, Greenhorn, and Graneros (Kcg) Fms, undivided
Arkosic sandstone, conglomerate, and shale. Includes Green Mountain Conglomerate south of Golden
Pierre Shale, undivided
Mainly intermediate to felsic compositions; some mafic
Mainly Lower Cretaceous, Jurassic, and Triassic Fms
Includes dune sand and silt and Peoria Loess