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Stony Creek Granite Gneiss plus Narragansett Pier Granite

Stony Creek Granite Gneiss plus Narragansett Pier Granite - Stony Creek Granite Gneiss - Red to pink, unevenly medium to very coarse grained, variably foliated granite or granite gneiss, composed of oligoclase, K-feldspar, and quartz with minor biotite and magnetite, sporatic garnet (in foliated varieties), and local muscovite. Commonly contains granite and pegmatite of Narragansett Pier type (and probably age). In much of area both granites occur as innumerable veins penetrating other units or as larger bodies full of inclusions of those units, which can be mapped through the bodies of granite. Narragansett Pier Granite (Permian) - Pink to red, medium- to coarse-grained (commonly pegmatitic), generally massive (not gneissic) granite, composed of microcline, oligoclase, quartz, and biotite, and accessory muscovite and magnetite. Considerable associated pegmatite.
State Connecticut
Name Stony Creek Granite Gneiss plus Narragansett Pier Granite
Geologic age Proterozoic Z? and Permian
Comments Part of Eastern Uplands; Avalonian (Continental) Terrane. Units are described seperately on printed map; combined in digital map.
Primary rock type granitic gneiss
Secondary rock type granite
Other rock types pegmatite
Lithologic constituents
Major
Metamorphic > GneissStony Creek Granite Gneiss - Red to pink, unevenly medium to very coarse grained, variably foliated granite or granite gneiss, composed of oligoclase, K-feldspar, and quartz with minor biotite and magnetite, sporatic garnet (in foliated varieties), and local muscovite.
Igneous > Plutonic > Granitic > GraniteNarragansett Pier Granite - Pink to red, medium- to coarse-grained (commonly pegmatitic), generally massive (not gneissic) granite, composed of microcline, oligoclase, quartz, and biotite, and accessory muscovite and magnetite.
Minor
Igneous > Plutonic > Granitic > Leucocratic-granitic > PegmatiteNarragansett Pier Granite - Considerable associated pegmatite.
Map references
Connecticut Geological and Natural History Survey, DEP, in cooperation with the U.S. Geological Survey, 2000, Bedrock Geology of Connecticut, data format: shapefile, file name: bedrock, downloaded from: http://magic.lib.uconn.edu/cgi-bin/MAGIC_DBsearch2.pl?Geography=37800&Loc=0000 on 9/18/2003, scale 1:50,000.
Unit references
Rodgers, John, compiler, 1985, Bedrock Geological Map of Connecticut: Connecticut Geological and Natural History Survey, Hartford, Connecticut, 2 sheets, scale 125,000.
Counties New Haven