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Original Oil in Place

Volume of oil originally in a reservoir (in stock-tank barrels).

Formula

OOIP = \frac{7758 \, A h \phi (1 - S_w)}{B_o}

Variables

OOIPOil in place (STB)

AArea (acres)

hNet pay (ft)

\phiPorosity

S_wWater saturation

B_oFormation volume factor

Example

A=640, h=50, φ=0.2, S_w=0.3, B_o=1.2: OOIP ≈ 28.9 MMSTB

Did You Know?

The constant 7758 is the number of barrels in one acre-foot of rock.

petroleum ooip reservoir

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