Compressibility drive in gas reservoirs

Input(s)

G: Gas in place (MSCF)

$G_{P}$: Gas Produced (MSCF)

$B_{g}$: Gas Formation Volume Factor $\left(\mathrm{MSCF} / \mathrm{ft}^{3}\right)$

$E_{f}$: Gas Compressibility Drive $\left(\mathrm{ft}^{3} / \mathrm{MSCF}\right)$

Output(s)

CI: Compressibility Index (dimensionless)

Formula(s)

$$ C I=\frac{G * E_{f}}{B_{g} * G_{P}} $$

Reference(s)

Ahmed, T., McKinney, P.D. Advanced Reservoir Engineering, Gulf Publishing House, Burlington, MA, 2015.