Pawlet Formation

Light-gray, tan-weathering, mica-speckled, massive to thin-bedded quartz-plagioclase wacke interbedded with dark-gray carbonaceous slate. Contains distinctive autoclastic chips of gray slate, fragments of dacitic to andesitic volcanics, and subangular clasts of dark-gray quartz and oligoclase. Interbedded black slates contain graptolites of the C. bicornis Biozone (see Webby and others, 2004, fig. 2.1) (lower to middle Mohawkian). Interpreted as uncomformable on rocks as old as the Hatch Hill Formation and possibly the West Castleton Formation of the allochthon. Unit is indistinguishable from beds in the Austin Glen Graywacke (after Potter, 1972) (Oag) interpreted as synorogenic autochthonous rocks. Rocks of the Giddings Brook, Sunset Lake, and Bird Mountain slices. Part of the Taconic Allochthon.
State Vermont
Name Pawlet Formation
Geologic age Upper Ordovician
Lithologic constituents
Major
Sedimentary > Clastic > Sandstone > GraywackeLight-gray, tan-weathering, mica-speckled, massive to thin-bedded quartz-plagioclase wacke.
Metamorphic > Metasedimentary > Metaclastic > SlateDark-gray carbonaceous slate.
Incidental
Igneous > Volcanic > Mafic-volcanic > AndesiteAutoclastic chips of gray slate, fragments of dacitic to andesitic volcanics.
Igneous > Volcanic > Felsic-volcanic > DaciteAutoclastic chips of gray slate, fragments of dacitic to andesitic volcanics.
References
NGMDB product
Counties Bennington - Rutland