| State | New Hampshire |
|---|---|
| Name | Granite, granodiorite, and tonalite |
| Geologic age | Late Ordovician |
| Lithologic constituents | Major
Igneous > Plutonic > Granitic > Granodiorite (Pluton)
Igneous > Plutonic > Granitic > Tonalite (Pluton)
Igneous > Plutonic > Granitic > Granite (Pluton)
|
| 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. |
| 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, 2 sheets, scale 1:250,000.https://ngmdb.usgs.gov/Prodesc/proddesc_37338.htm 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 | Cheshire |