Arkosic sandstone, conglomerate, and shale. Includes Green Mountain Conglomerate south of Golden
Includes Pikes Peak, Mount Rosa, Windy Point, and Redskin Granites and unnamed rocks
East: Ashy claystone and sandstone. Includes Castle Rock Conglomerate in region southeast of Denver. Northwest: Ashy claystone in North Park
Includes Slocum, Verdos, Rocky Flats, and Nussbaum Alluviums in east, and Florida, Bridgetimber, and Bayfield Gravels in southwest
Locally contains minor hornblende gneiss, calc-silicate rock, quartzite, and marble. Derived principally from sedimentary rocks
Includes Broadway and Louviers Alluviums
Arkosic sandstone, shale, mudstone, conglomerate, and local coal beds
Includes Piney Creek Alluvium and younger deposits
Arkosic sandstone and conglomerate
Early ash-flow tuff of Sawatch Range provenance
Includes dune sand and silt and Peoria Loess
Pierre Shale, undivided
Red siltstone, sandstone, and conglomerate
Consists of Niobrara Formation (Kn) and either Benton Shale or Carlile, Greenhorn, and Graneros Fms (Kcg)
Laramie Fm and Fox Hills Sandstone
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
Leadville Limestone, Williams Canyon Limestone , Manitou Limestone, and Sawatch Quartzite
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
Lykins Fm and Lyons Sandstone
Pierre Shale--Upper unit
Sharon Springs Member (organic-rich shale and numerous bentonite beds) in lower part
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
Williams Canyon Limestone, Manitou Limestone, and Sawatch Quartzite