Newburyport Complex

Gray, medium-grained tonalite and granodiorite.
State New Hampshire
Name Newburyport Complex
Geologic age early Late Silurian
Lithologic constituents
Major
Igneous > Plutonic > Granitic > Tonalite
Igneous > Plutonic > Granitic > Granodiorite
Comments Newburyport Complex = 450+/-15 U/Pb per NH043. 418+/-1 U/Pb per W.A. Bothner and S.A. Bowring, oral commun., Feb. 1994.
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 Naylor, R.S., 1984, Structural implications of some radiometric ages of igneous rocks in southeasten New england: Geological Society of America Bulletin, v. 95, p. 522-539.

NGMDB product
Counties Rockingham