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It should not be confused with Hydrocarbon Deposit which is a part of Petroleum Reservoir with dominating saturation by petroleum hydrocarbons.
Apart from Hydrocarbon Deposit the Petroleum Reservoir may include Formation water and Injection water and other fluids under anthropogenic activities.
Its structure and properties are described by Depositional facies, Lithological facies and Petrophysical rock properties and fluid properties of petroleum reservoir fluids.
The size, structure and complexity of Petroleum Reservoirs are normally characterized by the generally accepted metrics on Hydrocarbon Reserves Classification.
Petroleum Reservoir may share volume between three types of connected subsurface reservoirs:
See Also
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Petroleum Industry / Upstream / Subsurface E&P Disciplines / Petroleum Geology
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