Africa Oil Corp (AOIFF)

[Sweden1]

google translate

Description of procedure for the calculation of reservoir volume:
http://en.wikipedia.org/wiki/STOIIP

To calculate the volume you need the following data:
- Porosity - This is given in May and the presentation is 23-29%
- Water saturation - When oil / gas migrates into a trap pushes the water out that was there before. Unfortunately, stuff it does not squeeze out everything and a certain percentage of the pores is filled with water. Water saturation is not given but is usually about 30%
- Shrink factor (Bo) - When transporting the oil from an oil field reduces the pressure around the oil significantly. Lightweight components of the oil will then go over to the gaseous state and the volume of oil will be reduced. This factor is not given, and typically vary from 1-2. Assuming only that this is not significantly large and set it to 1.24
- Net two wholesale - used to convert from gross to net pay. For Ngamia is gross pay 650 m and net pay about 100 m in upper lokhone. It gives N / G at 0154 pm, according to the lower lokhone have similar N / G.
then the key element of uncertainty:
- Bulk-rock volume - volume of the trap. There are always used gross pay to enter the trap height and therefore needed N / G. The volume of the trap can varriere powerful if you have uncertain data and are therefore the most important element of uncertainty. A straightforward way to calculate the volume may be to assume that the trap is a perfect cone (this is of course wrong, but can give an indication of the volume). This will give us the following formula for the volume: V = (pi * r2 * gross pay) / 3, pi * r2 is the area of ??common bottom line and are given in AOIs March presentation is P50 - 5 km 2 and P10 - 18 km2 ( assume it is from March 19ende the engineer's Congress, the number of about 20km2).

(Bulk rock * N / G * por * (1 - water sat)) / shrink factor

Thus we get two calculations:
P50:
Bulk rock = (5 million m2 (0.65 0.14)) / 3 = 1 317 million m3

(1317 * 0154 * 0.23 * (1 - 0.3)) / 1.24 = 26 million m3 = 165.5 mmbo

P10:
Bulk rock = (18 million m2 (0.65 0.14)) / 3 = 4740 million m3
(4740 * 0154 * 0.29 * (1 - 0.3)) / 1.24 = 119.5 m3 = 751.6 mmbo

Thus, this calculation of size Ngamia between 165.5 to 751.6 mmbo. But remember this is based on an assumption that the field is a perfect cone, and is also based on area estimate from AOI in March presentation.

This is a relatively conservative calculation. When a cone is likely to underestimate the volume of the trap. I guess at least regarding that it is unlikely that it overestimates the volume of the trap. I will calculate a new maximum estimate later that exit from the trap is cylindrical. This will most likely effect of P10 lie between these two high estimates