Includes dune sand and silt and Peoria Loess
Arkosic sandstone, shale, mudstone, conglomerate, and local coal beds
Includes Piney Creek Alluvium and younger deposits
Sandstone, mudstone, claystone, and conglomerate; Denver is characterized by andesitic materials
Includes Broadway and Louviers Alluviums
Includes Slocum, Verdos, Rocky Flats, and Nussbaum Alluviums in east, and Florida, Bridgetimber, and Bayfield Gravels in southwest