Input

Main reserves inputs

The Input option requires definition of the following parameters:

  • Oil In Place / Gas In Place: Oil or gas volume in place in stock-tank volume (STOOIP).
  • Reservoir Area: Areal extent of the reservoir. For the Input method the Reservoir Area only has an effect if the Well Spacing option is selected in the reservoir Details Tab (Reservoir) and well reserves therefore are calculated based on the ratio between well drainage area and Reservoir Area.
  • Recovery Factor: Percentage of total Oil In Place or Gas In Place that can be recovered. For a Gas reservoir gas reservoir, you can specify the recovery factor to be calculated as a function of pressure in the Pressure Info Tab: if the Abandonment Pressure option is selected, the recovery factor is calculated from the difference between the Initial Pressure and the Abandonment Pressure and cannot be edited. Also, if the Gas Injection Modification option is checked in the Well Communication Tab the Recovery Factor is deduced from the injection modification table and is not editable here.
  • Probability of Success: Probability that recoverable oil / gas assume the input value; otherwise it will be zero, i.e. no success. This will only have an impact in Monte Carlo and Reservoir Monte Carlo runs. Since POS is in itself a probabilistic factor (of the Bernoulli type), it is not possible to define yet another probability distribution; the distribution button is hidden. The list of variables with distribution in the Monte Carlo window will include a Success factor whose distribution is determined by the Probability of Success.
Probability of Success cannot be defined as a function a variable with a defined distribution, because POS by itself defines a Bernoulli distribution.