|Name||Sweetheart Mountain Member [of Collinsville Formation]|
|Geologic age||Middle Ordovician|
Metamorphic > SchistGray and silvery (not rusty), medium- to coarse-grained, poorly layered schist, composed of quartz, oligoclase, biotite, muscovite, and garnet, and in places kyanite or sillimanite.
Metamorphic > Amphibolite
Metamorphiclayers of quartz-spessartine rock (coticule).
|Comments||Part of Central Lowlands; Iapetus (Oceanic) Terrane - Connecticut Valley Synclinorium; Gneiss Dome Belt, Hawley Formation and equivalent formations (includes Collinsville Formation) (Middle Ordovician). Secondary unit description per CT008.|
Rodgers, John, compiler, 1985, Bedrock Geological Map of Connecticut: Connecticut Geological and Natural History Survey, Hartford, Connecticut, 2 sheets, scale 1:125,000.
Simpson, H.E., 1990, Bedrock geology of the Bristol quadrangle, Hartford, Litchfield, and New Haven Counties, Connecticut: U.S. Geological Survey Bulletin, 1573, 13 p.
|Counties||Hartford - Litchfield|