Reliable field gas initially in place (FGIIP) estimation is achieved by performing multiple reservoir-pressure/gas-compressibility (P/Z) calculations. Several scenarios are developed in the complete paper by defining key areas based on permeability variation, areal distribution, and pressure/volume/temperature (PVT) behavior. The best FGIIP estimation is then fed back into the static model to generate numerous realizations considering the static uncertainties to produce the same FGIIP. A giant onshore gas field is highly heterogeneous, with permeability, lateral composition variation, and dynamic interaction between wells. Incorporating the correct estimation of FGIIP into the integrated asset model (IAM) has helped yield reliable forecasting and has enabled more-efficient field development.
Introduction
Reservoir A produces onshore from a limestone formation in the lower cretaceous horizon.