Basal member [of The Straits Schist] (CTStb;0)

Basal member [of The Straits Schist] ( = Russell Mountain Formation of Massachusetts) - Distinguished by presence of layers of amphibolite, marble, calc-silicate rock, and quartzite within more uniform schist like that on either side. Minor, unevenly distributed mineralization in W, Bi, Cu, Ni, and other metals.

State	Connecticut
Name	Basal member [of The Straits Schist]
Geologic age	Silurian
Original map label	Stb
Comments	Part of Central Lowlands; Iapetus (Oceanic) Terrane - Connecticut Valley Synclinorium; Hartland Belt
Primary rock type	schist
Secondary rock type	amphibolite
Other rock types	marble; calc-silicate rock; quartzite
Lithologic constituents	Minor Metamorphic > Schist Metamorphic > Metasedimentary > Metaclastic > Quartzite Metamorphic > Metasedimentary > Calc-silicate-rockcalc-silicate rock Metamorphic > Metasedimentary > Metacarbonate > Marble Metamorphic > Amphibolite
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. [http://magic.lib.uconn.edu/connecticut_data.html#environmental] [http://magic.lib.uconn.edu/cgi-bin/MAGIC_DBsearch2.pl?Geography=37800&Loc=0000]
Unit references	Rodgers, John, compiler, 1985, Bedrock Geological Map of Connecticut: Connecticut Geological and Natural History Survey, Hartford, Connecticut, 2 sheets, scale 125,000.
Geographic coverage	Fairfield - Hartford - Litchfield - New Haven