| State | Colorado |
|---|---|
| Name | Pre-ash-flow andesitic lavas, breccias, tuffs, and conglomerates |
| Geologic age | Tertiary |
| Lithologic constituents |
Major
Igneous > Volcanic > Mafic-volcanic > Andesite
Minor
Igneous (Pyroclastic-tuff)
Sedimentary > Clastic > Conglomerate
Igneous > Volcanic (Volcaniclastic-volcanic breccia)
|
| References | Tweto, Ogden, 1979, Geologic Map of Colorado: U.S. Geological Survey Special Geologic Map, scale 1:500,000. |
| NGMDB product | |
| Counties | Alamosa - Archuleta - Chaffee - Conejos - Costilla - Custer - Dolores - Fremont - Gunnison - Hinsdale - Huerfano - Lake - Mineral - Montrose - Ouray - Park - Pitkin - Pueblo - Rio Grande - Saguache - San Juan - San Miguel - Teller |