Paxton Formation

Sulfidic magnesian biotite and magnesian cordierite schist and sillimanite quartzite. The Paxton, here of group rank, includes strata formerly mapped in CT as the Hebron Formation and in MA as the Paxton Formation. It conformably overlies the Oakdale Formation and structurally and conformably underlies the Brimfield Group. It is undivided in central MA; in northeast CT and adjacent MA it is divided into the Dudley and Southbridge Formations. Age is Late Proterozoic(?) based on the intrusion of 440 m.y. Hedgehog Hill gneiss into the overlying Brimfield Group and an age of 1188 m.y. for detrital zircons from the Paxton (Pease, 1989).
State Massachusetts
Name Paxton Formation
Geologic age Silurian
Lithologic constituents
Major
Metamorphic > Metasedimentary > Metaclastic > Quartzitesillimanite quartzite
Metamorphic > Schistsulfidic magnesian biotite and magnesian cordierite schist
Comments Part of Merrimack Belt (Silurian, Devonian and Pennsylvanian Rocks). Secondary unit description per MA009.
References
NGMDB product
Counties Hampden - Worcester