Volumetric Method To Estimate Volume In Place and Reserves

Volumetric is a method to estimate fluid in reservoir based on volume of pore space in a rock and water saturation.

Volume of Oil Initially In Place (OIIP)

To estimate oil initially volume in place, the following formula is a volumetric calculation for oil.



STOIIP = stock tank oil in place, stb

A= area, acre

h = reservoir thickness, ft

ɸ = rock porosity, %

Swc =connate water saturation, %

Boi = oil formation volume factor, rb/stb

Note: the stock tank condition is a standard surface condition of oil and gas at 60F and 14.7 psia. Continue reading