Monastery Formation

Heterogeneous unit consisting of coarse-grained, gray- to rusty-brown-weathering garnet-biotite-muscovite-quartz schist, gray albitic biotite-quartz granofels, well-bedded light-gray to steel-gray biotite, minor epidote-magnetite-actinolite-chlorite feldspathic wacke, and, near base, grayish-green laminated chlorite-muscovite-albite granofels and phyllite. Unit mapped in Hancock and Ripton in part as lateral equivalent of the Tyson Formation to the south and the Underhill Formation to the north. Eastern flank of the Green Mountain massif and eastern domes.
State Vermont
Name Monastery Formation
Geologic age Cambrian and Neoproterozoic
Lithologic constituents
Major
Metamorphic > Granoblastic > GranofelsGray albitic biotite-quartz granofels and, near base, grayish-green laminated chlorite-muscovite-albite granofels and phyllite.
Metamorphic > Schist > Mica-schistCoarse-grained, gray- to rusty-brown-weathering garnet-biotite-muscovite-quartz schist.
Sedimentary > Clastic > Sandstone > Graywacke (Bed)Well-bedded light-gray to steel-gray biotite, minor epidote-magnetite-actinolite-chlorite feldspathic wacke.
Minor
Metamorphic > Metasedimentary > Metaclastic > PhylliteNear base, grayish-green laminated chlorite-muscovite-albite granofels and phyllite.
References
NGMDB product
Counties Addison - Chittenden - Rutland - Washington