Dalton Formation (CTCAd;0)

Dalton Formation

(Including Poughquag and Lowerre Formation) - Gray, tan-weathering, medium-grained, generally well layered gneiss or feldspathic quartzite, composed of quartz, microcline, plagioclase, muscovite, biotite, and generally tourmaline; some schistose micaceous layers have sillimanite; commonly as quartz-sillimanite nodules rimmed with muscovite. Layers of purer quartzite in many areas, especially near the top or where the formation is thin.

State	Connecticut
Name	Dalton Formation
Geologic age	Lower Cambrian and perhaps partly older
Lithologic constituents	Major Metamorphic > Metasedimentary > Metaclastic > Quartzitefeldspathic quartzite; layers of purer quartzite in many areas, especially near the top or where the formation is thin. Metamorphic > GneissComposed of quartz, microcline, plagioclase, muscovite, biotite, and generally tourmaline; some schistose micaceous layers have sillimanite; commonly as quartz-sillimanite nodules rimmed with muscovite.
Comments	Part of Western Uplands; Proto-North American (Continental) Terrane - Carbonate Shelf
References	Rodgers, John, compiler, 1985, Bedrock Geological Map of Connecticut: Connecticut Geological and Natural History Survey, Hartford, Connecticut, 2 sheets, scale 1:125,000.
NGMDB product	NGMDB product page for 54245
Counties	Fairfield - Litchfield

Dalton Formation

Rodgers, John, compiler, 1985, Bedrock Geological Map of Connecticut: Connecticut Geological and Natural History Survey, Hartford, Connecticut, 2 sheets, scale 1:125,000.