Family, First
Petroleum Engineering 311
MQ 8
(open notes)
1) The relative permeability of the reservoir rock to oil is reported for oil saturation 0.45 and water saturation 0.25.
The value reported is k ro (0.45,0.2) = 0.18. You want to figure out the effective permeability to oil (in md) at the given
saturation state.
You know that the absolute permeability of the rock is 0.86 md, the permeability of the rock to air is 1.45 md
(measured at low pressure), you know that the wetting phase is water, you know that the irreducible water saturation
is 0.15 and you know that somebody measured the effective permeability to oil at 0.15 water and zero gas saturation
and found 0.31 md. Unfortunately, you do not know what definition was used when k ro (0.45,0.2) = 0.18 was measured and calculated.
Now you are to prepare a table with two columns. In the first column you write an assumption, in the second column you write the effective permeability to oil according to the assumption. (You may add rows.)
Assumption
Effective perm to oil, md
The lab used the absolute permeability of the rock as the base.
0.15
The lab used the air permeability of the rock as the base.
0.26
The lab used the relative permeability of the rock to oil at irreducible water saturation and no gas present.
0.056