Ammonoosuc Volcanics of Billings (1935) - metarhyolite tuff, lapilli tuff, tuff breccia, and lava (VTOar;0)

Ammonoosuc Volcanics of Billings (1935) - metarhyolite tuff, lapilli tuff, tuff breccia, and lava

Greenish-gray, light-bluish-gray, or medium-bluish-gray metarhyolite tuff, lapilli tuff, tuff breccia, and lava. Generally porphyritic with 5 to 20 percent plagioclase and, in some places, quartz phenocrysts. Generally strongly foliated with waxy sheen on foliation surfaces. Stratified rocks of the Bronson Hill arch and Sawyer Mountain belt.

State	Vermont
Name	Ammonoosuc Volcanics of Billings (1935) - metarhyolite tuff, lapilli tuff, tuff breccia, and lava
Geologic age	Upper and Middle Ordovician
Lithologic constituents	Major Metamorphic > Metaigneous > Metavolcanic > MetarhyoliteGreenish-gray, light-bluish-gray, or medium-bluish-gray metarhyolite tuff, lapilli tuff, tuff breccia, and lava. Generally porphyritic with 5 to 20 percent plagioclase and, in some places, quartz phenocrysts. Generally strongly foliated with waxy sheen on foliation surfaces.
References	Ratcliffe, N.M., Stanley, R.S., Gale., M.H., Thompson, P.J., and Walsh, G.J., 2011, Bedrock geologic map of Vermont: U.S. Geological Survey Scientific Investigations Map 3184, 3 sheets, scale 1:100,000. https://pubs.er.usgs.gov/publication/sim3184
NGMDB product	NGMDB product page for 96860
Counties	Caledonia - Essex - Orange

Ammonoosuc Volcanics of Billings (1935) - metarhyolite tuff, lapilli tuff, tuff breccia, and lava

Ratcliffe, N.M., Stanley, R.S., Gale., M.H., Thompson, P.J., and Walsh, G.J., 2011, Bedrock geologic map of Vermont: U.S. Geological Survey Scientific Investigations Map 3184, 3 sheets, scale 1:100,000.