Volumetric equation

The expression for total in-place hydrocarbon volume V, according to the equation (for oil):


 * $$V = A \times T \times G \times \phi \times N\!\!:\!\!G \times S_\mathrm{O} \times \frac{1}{B_\mathrm{O}} $$


 * Area A: The mapped area of the prospect.


 * Thickness T: The average stratigraphic thickness of the gross reservoir interval


 * Geometric correction factor G: Based on the column height and the gross sectional shape of the prospect.


 * Porosity &phi;: As a decimal fraction.


 * Net to gross N:G: As a decimal fraction.


 * Oil saturation SO: As a decimal fraction. Values of 0.5 to 0.9 are typical.


 * Volume factor BO: The formation volume factor, or shrinkage factor, is the ratio of a barrel of oil in reservoir conditions to the same oil in surface (so-called stock-tank) conditions: 25&deg;C and 1 atm. Typical values are between 1 and 1.7.