Hook Mountain Basalt-
Lower Jurassic
2 major flows
maximum thickness 110 m
Preakness Basalt-
Lower Jurassic-
3-4 major flowsof basalt, types vary from columnar through amygdaloidal and pillow formation
maximum thickness to 320 m
Orange Mountain Basalt-
Lower Jurassic-
3 major flows of basalt of various forms
maximum thickness 182 m
Diabase Intrusives-
dikes of intrusive diabase which make up the Palisades and other sills and dikes of the region
minerals usually restricted to vein fillings
Traprock Formations of the Region