Oil in place is the total hydrocarbon content of an
oil reservoir and is often abbreviated STOOIP, which stands for Stock Tank Original Oil In Place, or STOIIP for Stock Tank Oil Initially In Place, referring to the oil in place before the commencement of production. In this case, stock tank refers to the storage vessel (often purely notional) containing the oil after production. Oil in place must not be confused with
oil reserves, that are the technically and economically recoverable portion of oil volume in the reservoir.
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the amount of crude oil that is estimated to exist in a reservoir and that has not been produced.
The estimation of the real amount of oil in a reservoir, and so a higher figure than the recoverable reserves of the reservoir.