Cram Hill Formation - undivided

Predominantly dark-gray to grayish-green quartz-chlorite-(biotite)-muscovite phyllite; contains 1- to 2-cm-thick beds of dark-gray metasiltstone and quartzite, and thicker beds of dark-bluish-gray vitreous quartzite, grayish-green to light-yellowish-green sericite phyllite (felsic tuffs) and cobble to boulder conglomerate, and greenstone. Mapped north of the Braintree Intrusive Complex and near Brattleboro. Part of the metasedimentary host rocks of the North River Igneous Suite. Cram Hill Formation: western part of the Cram Hill Formation is in part correlative with Whetstone Hill Member of the Moretown Formation. Rocks of the Early to Late Taconic Accreted Terrane of the Rowe-Hawley Zone. Eastern allochthonous sequence, oceanic and accretionary realm, ultramafic inclusions, volcanic-arc intrusives, and volcanic rocks.
State Vermont
Name Cram Hill Formation - undivided
Geologic age Middle? and Early Ordovician
Lithologic constituents
Major
Metamorphic > Metasedimentary > Metaclastic > PhyllitePredominantly dark-gray to grayish-green quartz-chlorite-(biotite)-muscovite phyllite; contains 1- to 2-cm-thick beds of dark-gray metasiltstone and quartzite. Grayish-green to light-yellowish-green sericite phyllite (felsic tuffs).
Minor
Sedimentary > Clastic > ConglomerateCobble to boulder conglomerate.
Metamorphic > Metasedimentary > Metaclastic > QuartziteDark-bluish-gray vitreous quartzite.
Metamorphic > Metaigneous > Greenstone
Incidental
Metamorphic > Metasedimentary > Metaclastic > MetasiltstonePredominantly dark-gray to grayish-green quartz-chlorite-(biotite)-muscovite phyllite; contains 1- to 2-cm-thick beds of dark-gray metasiltstone and quartzite.
References
NGMDB product
Counties Orange - Orleans - Washington - Windham