Basalt flows and associated tuff, breccia, and conglomerate of late-volcanic bimodal suite

Includes basalts of Hinsdale Fm in San Juan Mountains - Servilleta Fm in San Luis Valley and many other occurrences
State Colorado
Name Basalt flows and associated tuff, breccia, and conglomerate of late-volcanic bimodal suite
Geologic age Tertiary
Lithologic constituents
Major
Igneous > Volcanic > Mafic-volcanic > Basalt
Minor
Igneous > Volcanic (Volcaniclastic-volcanic breccia, Pyroclastic-tuff)
Sedimentary > Clastic > Conglomerate
References

Tweto, Ogden, 1979, Geologic Map of Colorado: U.S. Geological Survey Special Geologic Map, scale 1:500,000.

NGMDB product
Counties Archuleta - Baca - Chaffee - Conejos - Costilla - Custer - Delta - Eagle - Fremont - Garfield - Grand - Gunnison - Hinsdale - Las Animas - Mesa - Mineral - Moffat - Park - Rio Blanco - Rio Grande - Routt - Saguache