Percentage of currently recovered  hydrocarbon reserves  from the Surface Tank Hydrocarbon Initial In Place (STHCIIP):

{\rm RF}(t) = \frac{{Q_{HC}}(t)}{{\rm V_{\rm STHCIIP}}} \cdot 100 \%

It always ranges  and is related to Depletion Factor (DF) as:

{\rm RF} (t) = {\rm EURF} \cdot {\rm DF}(t)

where EUR is Estimated Ultimate Recovery.

The Recovery Factor concept splits naturally into two categories: 

{\rm RFO} = \frac{Q^{\uparrow}_O}{V_{\rm STOIIP}}

{\rm RFG} = \frac{Q^{\uparrow}_G}{V_{\rm STGIIP}}

See Also

Petroleum Industry / Upstream /  Production / Subsurface Production / Field Study & Modelling / Production Analysis

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