Ammonoosuc Volcanics  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Paleozoic
 ...Ordovician
 ....Middle Ordovician
 .....Ammonoosuc Volcanics
RTVermont
 Massachusetts
 New Hampshire
SNNW New Hampshire, N central Massachusetts, and Vermont. Added to Thesaurus in 1985.