Refers to subsurface volume of all oil initially present in Petroleum Reservoir before the anthropogenic invasion.
The volumetric value of OIIP in NTP conditions is given by STOIIP.
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The changes in volume and structure of OIIP over time can be caused by production from a given petroleum reservoir or because of the by hydrocarbons migration caused by production at from the offset hydrodynamically connected petroleum reservoirs.
For the current volume and distribution of oil after the anthropogenic invasion refer to Oil In Place (OIP).
See Also
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Petroleum Industry / Upstream / Subsurface E&P Disciplines / ExplorationPetroleum Geology / Petroleum Reservoir / Booking Reserves[ Petroleum Reservoir Fluids / Hydrocarbon Initial In Place (HCIIP)
[ Exploration ] [ Booking Reserves ] [ Gas Oil Initial In Place (GIIPOIIP)] ][ Surface Stock-Tank Hydrocarbon Oil Initial In-Place (STHCIIPSTOIIP) ] [ Stock-Tank Mobile Oil Initial In-Place (STOIIPMOIIP) ]
[ Stock-Tank Gas Initial Oil In - Place (STGIIPOIP) ]