Holyoke Basalt

Thick, columnar quartz tholeiite containing local gabbroic segregations, thinks eastward; interpreted as one or more thick ponded lava flows. Assigned to Newark Supergroup (Robinson and Luttrell, 1985).
State Massachusetts
Name Holyoke Basalt
Geologic age Lower Jurassic
Lithologic constituents
Igneous > Volcanic > Mafic-volcanic > Basalt (Flow)columnar quartz tholeiite
Igneous > Plutonic > Gabbroic > Gabbro (Flow)containing local gabbroic segregations
Comments Part of Mesozoic Basins (Jurassic and Triassic Rocks); Sedimentary and Volcanic Rocks of Hartford Basin. Secondary unit description per MA003 as reported in USGS Geologic Names lexicon (ref. MA024)
NGMDB product
Counties Hampden - Hampshire