Iberville Formation

Dark-gray shale with thin discontinuous beds of crossbedded and graded dolomitic siltstone. Rocks of the Laurentian Margin. Part of the Adirondack lowlands and Lake Champlain lowlands (west of the Orwell and Champlain thrusts).
State Vermont
Name Iberville Formation
Geologic age Upper Ordovician
Lithologic constituents
Major
Sedimentary > Clastic > Mudstone > Shale (Bed)Dark-gray shale.
Minor
Sedimentary > Clastic > Siltstone (Bed)Thin discontinuous beds of crossbedded and graded dolomitic siltstone.
References
NGMDB product
Counties Addison - Chittenden - Franklin - Grand Isle