Hornblende granodiorite

Hornblende granodiorite.
State New Hampshire
Name Hornblende granodiorite
Geologic age Late Ordovician
Lithologic constituents
Igneous > Plutonic > Granitic > Granodiorite (Pluton)hornblende granodiorite
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. Landaff dome intrusive rocks of Oliverian Plutonic Suite = 444+/-8 U/Pb per NH020. 447+/-4 U/Pb per J.N. Aleinikoff, oral commun., Feb. 1994.

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.


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.

NGMDB product
Counties Grafton