Modelling PODS of petrophysical rock types in a carbonate field for dynamic calibration of a matrix-only reservoir model

Carbonate reservoirs are notoriously difficult to characterize. In some field cases it is difficult to determine whether the production is even coming from fractures or matrix. Modelling matrix properties in a reservoir is important to get right before fractures are added as carnbonates are notoriously variable. Flow characteristics of highly heterogeneous carbonates can appear like fractures. Many field studies show that the porosity patterns are very complex and heterogonous in carbonate reservoirs and it makes a nonunique correlation of porosity-permeability. We introduced a new concept for modeling this complicated reservoir systems based on identification of porosity patterns in the matrix and the use of an appropriate rock type (termed the PODS approach). This concept has been applied to a gas condensate carbonate reservoir with a high uncertainty in the porosity system - whether fractured or not. This study describes the history matching of a complex high angle well to production test to a model without fractures and thereby describes the quality of this matrix-only model.