You must log in to edit PetroWiki. Help with editing
Content of PetroWiki is intended for personal use only and to supplement, not replace, engineering judgment. SPE disclaims any and all liability for your use of such content. More information
Oil in place
Oil in place (OIP), or oil-in-place (not to be confused with original oil-in-place) is the estimated amount of oil in a reservoir. A variety of techniques, combined with mathematical equations, is used to determine OIP. Only a fraction of the OIP, called the recovery factor, can be recovered from a reservoir.
Estimation of oil in place
The technique used to estimate the OIP in a given reservoir depends on the type of reservoir and the stage of oil recovery.
Volumetric balance equation
When fluids are withdrawn from a petroleum reservoir, the space left behind is filled partly by the expansion of the remaining fluids and rock and partly by the flood of water from an adjacent aquifer, if there is one. The volumetric balance equation (VBE) is an expression of this statement. In simplified form, the VBE states:
- Z = AX = BY
where:
- Z= Total fluid withdrawals in MMRB
- A= Original Active Oil=in-Place in MMRB
- X= Unit Expansion
- B= Water Influx Constant
- Y= Water Influx function
Statistical confidence intervals
Restored-state method
Materials balance method
Production decline curve method
Software
References
Use this section for citation of items referenced in the text to show your sources. [The sources should be available to the reader, i.e., not an internal company document.]
Noteworthy papers in OnePetro
Use this section to list papers in OnePetro that a reader who wants to learn more should definitely read
External links
Use this section to provide links to relevant material on websites other than PetroWiki and OnePetro
See also
Use this section for links to related pages within PetroWiki, including a link to the original PEH text where appropriate