Mineral assessment tracts in Northumberland county, Pennsylvania

EC01: Sandstone-hosted Pb-Zn (30a) (Paleozoic) , covers 19 % of this area: The number of undiscovered deposits in this tract was not estimated.
EC04: Mississippi Valley, Appalachian Zn (32b) (Late Paleozoic) , covers 83 % of this area: The number of undiscovered deposits in this tract was not estimated.