Page 50 - Formulas and Calculations for Petroleum Engineering

Reservoir engineering formulas and calculations Chapter 1 43

Formula(s)
N B o
p
N ¼
S c +c f
w
wi
B B +B DP
o oi oi
1 S
wi
Reference: Ahmed, T., McKinney, P.D. 2005. Advanced Reservoir Engineering, Gulf Publishing of Elsevier, Chapter: 5,
Page: 333.
1.98 Oil in place in saturated oil reservoirs

Input(s)
N p : Cumulative Oil Production (STB)
B o : Oil Formation Volume Factor (bbl/STB)
G p : Cumulative Gas Production (MSCF)
R s : Gas Solubility (SCF/STB)
B g : Gas Formation Volume Factor (bbl/SCF)
B oi : Initial Oil Formation Volume Factor (bbl/STB)
R si : Initial Gas Solubility (SCF/STB)

Output(s)

N: Oil in Place (bbl)

Formula(s)

N B +G N R B
p o p p s g
N ¼
B B +R R Þ B
ð
o oi si s g
Reference: Ahmed, T., McKinney, P.D. 2005. Advanced Reservoir Engineering, Gulf Publishing of Elsevier, Chapter: 5,
Page: 334.

1.99 Oil lost in migration
Input(s)

h: Average Change in Depth of the Gas-Oil Contact (ft)
Ø: Porosity (fraction)
A: Average Cross-Sectional Area of the Gas-Oil Contact (acres)
S org : Residual Oil Saturation in The Gas Cap Shrinking Zone (fraction)
B oa : Oil Formation Volume Factor at Abandonment (bbl/STB)

Output(s)
O: Volume of Oil Lost (bbl)

Formula(s)
S org

O ¼ 7758 A h Ø
B
oa
Reference: Ahmed, T., McKinney, P.D. 2005. Advanced Reservoir Engineering, Gulf Publishing of Elsevier, Chapter: 5,
Page: 333.