Comparison of Predictions from Reservoir Models to Actual Production Data: Field Examples

摘要

Reservoir models were constructed on two gas condensatereservoirs (M-4/M4-A and M-6) in the Gulf of Mexico. Thegas reservoirs are at a depth of 15000 feet subsea, overpressured and supported by active aquifers. Initial gasproduction was essentially water-free with steep pressuredecline that was later followed by rapid rise in waterproduction. Peak gas production from either reservoir reachedabout 166 MMCFPD.The reservoir models were fully compositional. Themodels were history-matched with production data and thenused to predict future performance. This paper comparespredictions of the models to actual reservoir production data.The model for the M-6 reservoir predicted gas production withan accuracy of –0.72%, condensate production at +2.80% andwater production at +12.4%. The predicted accuracies for theM-4/4A reservoirs are as follows: gas (-0.33%), condensate (-4.99%) and water (+25.56%).The main objective of this paper is to provide data on theerrors associated with the use of history matched models toforecast reservoir performance. Surveys of the petroleumliterature indicate that they are few technical papers thatcompare model predictions to actual reservoir performancedata over an extended period of time. Mass publications ofthese types of results are essential in establishing reservoirsimulation as a valuable analytical tool for reservoir engineers.It will also improve its acceptance in the petroleum industry asa reliable tool for prediction of reservoir performance.