Biotite pegmatoid granitic gneiss

Extensive areas of biotite pegmatoid granitic gneiss, locally muscovite-bearing. Enclaves of metasedimentary units in these granites and associated gneisses are locally albitized and enriched in magnetite; enclaves of highly aluminous altered rocks now contain restites of chloritoid and abundant sericite. U-Pb zircon ages of 1,119±3.3 Ma (no. 15) and 1,121±1.4 Ma (no. 14) determined on samples near Sherburne Center and on Telegraph Hill east of Chittenden Reservoir by Karabinos and Aleinikoff (1990). Chittenden Intrusive Suite (1,149±8 Ma to 1,119±3 Ma). Mount Holly Complex intrusive rocks. Rocks of the Green Mountain and Lincoln Mountain massifs and eastern domes.
State Vermont
Name Biotite pegmatoid granitic gneiss
Geologic age Late Mesoproterozoic
Lithologic constituents
Major
Metamorphic > Metasedimentary > ParagneissExtensive areas of biotite pegmatoid granitic gneiss, locally muscovite-bearing.
Minor
Metamorphic > MetasedimentaryEnclaves of metasedimentary units in these granites and associated gneisses are locally albitized and enriched in magnetite; enclaves of highly aluminous altered rocks now contain restites of chloritoid and abundant sericite.
References
NGMDB product
Counties Rutland