Ammonoosuc Volcanics, Bimodal volcanic rocks

Ammonoosuc Volcanics, Bimodal volcanic rocks - Locally includes unmapped Oals.
State New Hampshire
Name Ammonoosuc Volcanics, Bimodal volcanic rocks
Geologic age Middle - Upper Ordovician
Lithologic constituents
Igneous > Volcanic > Felsic-volcanicbimodal volcanic rocks
Igneous > Volcanic > Mafic-volcanicbimodal volcanic rocks
Comments Part of the Central Maine Composite Terrane (Central Maine Trough) - Variably metamorphosed sedimentary and volcanic rocks of greenschist to granulite facies, locally migmatized. Area includes structural belts between the Monroe fault on the west and the Campbell Hill fault on the east; that is, the Bronson Hill anticlinorium, Piedmont allochthon, Kearsarge-central Maine synclinorium, central New Hampshire anticlinorium, and Rochester-Lebanon (Maine) antiformal synclinorium. Ammonoosuc Volcanics = 461+/-8 U/Pb per J.N. Aleinikoff, oral commun., Feb. 1994.
NGMDB product
Counties Cheshire - Coos - Grafton - Sullivan