Fort Cassin Formation - Root Pond Quartzite Member

Light-gray to tannish-white, well-bedded and vitreous steel-gray quartzite interbedded with orangey-tan- and beige-weathering dolostone and thin beds of fossiliferous limestone. Named for occurrences near Root Pond in the Benson quadrangle, but herein extended to include thin lenses of quartzite that occur interbedded at several positions in the Fort Cassin Formation. Interbedded limestones contain upper Ibexian conodonts southwest of Root Pond (J.E. Repetski, USGS, written commun., 2004). Part of the Beekmantown Group. Rocks of the Laurentian Margin. Part of the Adirondack lowlands and Lake Champlain lowlands (west of the Orwell and Champlain thrusts).
State Vermont
Name Fort Cassin Formation - Root Pond Quartzite Member
Geologic age Middle and Lower Ordovician
Lithologic constituents
Major
Metamorphic > Metasedimentary > Metaclastic > QuartziteLight-gray to tannish-white, well-bedded and vitreous steel-gray quartzite.
Minor
Sedimentary > Carbonate > Limestone (Bed)Interbedded with orangey-tan- and beige-weathering dolostone and thin beds of fossiliferous limestone.
Sedimentary > Carbonate > Dolostone (Bed)Interbedded with orangey-tan- and beige-weathering dolostone and thin beds of fossiliferous limestone.
References
NGMDB product
Counties Rutland