Buttress Dolerite (uncertain) (CTJb1;0)

Buttress Dolerite (uncertain)

Dark-gray to greenish-gray (weathers brown or gray), medium- to fine-grained, commonly porphyritic, generally massive with well-developed columnar jointing, grading from basalt near contacts to fine-grained gabbro in the interior, composed of plagioclase and pyroxene with accessory opaques and locally devitrified glass, quartz, or olivine.

State	Connecticut
Name	Buttress Dolerite (uncertain)
Geologic age	Middle? Jurassic
Lithologic constituents	Major Igneous > Plutonic > Gabbroic > Gabbro (Diabase)Dark-gray to greenish-gray (weathers bright orange to brown), medium- to fine-grained, grading from basalt near contacts to fine-grained gabbro in the interior, generally massive with well-developed columnar jointing, composed of plagioclase and pyroxene with accessory opaques and locally devitrified glass, quartz, or olivine. Igneous > Volcanic > Mafic-volcanic > Basalt (Diabase)Dark-gray to greenish-gray (weathers bright orange to brown), medium- to fine-grained, grading from basalt near contacts to fine-grained gabbro in the interior, generally massive with well-developed columnar jointing, composed of plagioclase and pyroxene with accessory opaques and locally devitrified glass, quartz, or olivine.
Comments	Part of Central Lowlands; Newark Terrane - Hartford and Pomperaug Mesozoic Basins; Same as Jb
References	Rodgers, John, compiler, 1985, Bedrock Geological Map of Connecticut: Connecticut Geological and Natural History Survey, Hartford, Connecticut, 2 sheets, scale 1:125,000.
NGMDB product	NGMDB product page for 54245
Counties	New Haven

Buttress Dolerite (uncertain)

Rodgers, John, compiler, 1985, Bedrock Geological Map of Connecticut: Connecticut Geological and Natural History Survey, Hartford, Connecticut, 2 sheets, scale 1:125,000.