The Virgilian series is the youngest part of the
Pennsylvanianepoch in the
North American geologic classification series.[1] During Virgilian times, the top of the Conemaugh and the entire Monongahela group were deposited.[2] As with other
Carboniferous series, it comprises
cyclothems, or distinct cycles of
sedimentary rock formation.
Monongahela cyclothems (youngest at top)
Note: the names below are of the Conemaugh age, not Monongahela age