Refers to all oil currently present in Petroleum Reservoir.
The volumetric value of OIP in NTP conditions is given by STOIP.
The changes in volume and structure of OIP over time can be caused by production from a given petroleum reservoir or because of the hydrocarbons migration caused by production from the remote hydrodynamically connected petroleum reservoirs.
For the initial volume and distribution of oil existed before the anthropogenic invasion refer to Oil Initial In Place (OIIP).
See Also
Petroleum Industry / Upstream / Subsurface E&P Disciplines / Petroleum Geology / Petroleum Reservoir / Petroleum Reservoir Fluids / Hydrocarbon In Place (HCIP)
[ Exploration ] [ Booking Reserves ] [ Stock-Tank Oil In-Place (STOIP) ]