Preakness Basalt from the Newark rift basin. LEFT: Sketch of composite section of Preakness Basalt exposed in roadcut of I-280 in West Orange, NJ. Splintery prismatic jointing is a characteristic feature of the Preakness Basalt. From Olsen et al. (1989). RIGHT: Preakness Basalt with platy-prismatic jointing, at Dock Watch Hollow, Martinsville, NJ. From Olsen et al. (2016).
Preakness Basalt from the Newark rift basin