Granitic rocks of 1400-m.y. age group (COYg;0)

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

State	Colorado
Name	Granitic rocks of 1400-m.y. age group
Geologic age	Proterozoic \| Mesoproterozoic
Original map label	Yg
Primary rock type	granite
Secondary rock type	granodiorite
Other rock types	quartz monzonite
Lithologic constituents	Major Igneous > Plutonic > Granitic > Granite Igneous > Plutonic > Granitic > Alkali-feldspar-graniteincludes peraluminous granites Minor Igneous > Plutonic > Syenitic > Quartz-monzonite
Map references	Tweto, Ogden 1979, Geologic Map of Colorado: U.S. Geological Survey Special Geologic Map, scale 1:500,000.
Unit references	Tweto, Ogden 1979, Geologic Map of Colorado: U.S. Geological Survey Special Geologic Map, scale 1:500,000.
Geographic coverage	Archuleta - Boulder - Clear Creek - Costilla - Custer - Eagle - El Paso - Fremont - Grand - Gunnison - Hinsdale - Huerfano - Jackson - Jefferson - Lake - La Plata - Larimer - Mesa - Montrose - Park - Pitkin - Pueblo - Routt - Saguache - San Juan - Summit - Teller