Synonym: Net Pay = Main Pay
A portion of the Gross Pay which meets specific criteria for economical recovery (such as minimum porosity, permeability and hydrocarbon saturation)
Usually quantified as total thickness of all qualified reservoir elements or as the percentage of the total qualified thickness to Gross Pay.
See also
Petroleum Industry / Upstream / Subsurface E&P Disciplines / Petroleum Geology / Effective formation thickness / Gross Pay