Tonalite, diorite, granodiorite, and granite

More mafic rocks have hornblende; part of Lost Nation pluton.
State New Hampshire
Name Tonalite, diorite, granodiorite, and granite
Geologic age Late Ordovician
Lithologic constituents
Igneous > Plutonic > Granitic > Granodiorite (Pluton)
Igneous > Plutonic > Granitic > Tonalite (Pluton)
Igneous > Plutonic > Dioritic > Diorite (Pluton)
Igneous > Plutonic > Granitic > Granite (Pluton)
Comments Part of the Highlandcroft Plutonic Suite (Late Ordovician) - Pink to green rocks containing epidote, sericite, and chlorite. Found as stocks metamorphosed to greenschist facies and commonly sheared; coeval with Oliverian Plutonic Suite. Lost Nation pluton of Highlandcroft Plutonic Suite = 439+/-25 U/Pb per NH011; and 442+/-4 U/Pb per J.N. Aleinikoff, oral commun., June 30, 1988.

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, 2 sheets, scale 1:250,000.

Lyons, J.B., Aleinikoff, J.N., and Zartman, R.E., 1986, Uranium-thorium-lead ages of the Highland Plutonic Suite, New Hampshire: American Journal of Science, v. 286, p. 489-509.

NGMDB product
Counties Coos