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Granite, granodiorite, and tonalite

Granite, granodiorite, and tonalite.
State New Hampshire
Name Granite, granodiorite, and tonalite
Geologic age Late Ordovician
Comments Part of the Oliverian Plutonic Suite (Late Ordovician) - Pink, weakly to moderately foliated, locally porphyritic biotite granitoids found in mantled gneiss domes. Mafic varieties contain hornblends. Variably metamorphosed up to amphibolite facies. Oliverian Plutonic Suite: Keene and Surry dome intrusive rocks = 444+/-8 U/Pb per NH020. Warwick dome intrusive rocks = 444+/-8 U/Pb per NH020.
Primary rock type granite
Secondary rock type granodiorite
Other rock types tonalite
Lithologic constituents
Map references
Bennett, D. S, , Wittkop, C.A., and Dicken, C.L., 2006 , Bedrock Geologic Map of New Hampshire - A Digital Representation of the Lyons and others 1997 map and ancillary files: U.S. Geological Survey Data Series 215, scale 1:250,000, CD-ROM.
Unit references
Lyons, J.B., Bothner, W.A., Moench, R.H., and Thompson, J.B., Jr., 1997, Bedrock Geologic Map of New Hampshire: Reston, VA, U.S. Geological Survey Special Map, 1:250,000, 2 sheets.
Zartman, R.E., and Leo, G.W., 1985, New radiometric ages on gneisses of the Oliverian domes in New Hampshire and Massachusetts: American Journal of Science, v. 285, p. 267-280.
Counties Cheshire