Holyoke Basalt  search
BTChronostratigraphic Units
 .Phanerozoic
 ..Mesozoic
 ...Jurassic
 ....Lower Jurassic
 .....Holyoke Basalt
RTMassachusetts
 Connecticut
 Newark Supergroup
SNIn Newark Supergroup. Central Connecticut and central Massachusetts. Previously thought to be Upper Triassic in age. Added to Thesaurus in 1989.