Application of Petrophysically Derived 'Flow Facies' for Reservoir Characterization and Simulation: Wara Reservoir, Greater Burgan Field

摘要

In fluvially dominated delta plain reservoirs, such as the Wara formation in the Greater Burgan Field, characterizing a reservoir's flow properties accurately is essentilal in developing a sound reservoir mode. This is easier said than done. Typically, lithofacies identified in cores are correlated to multiple log suite characteristics. These are then used to help define simulation flow properties in wells. In Greater Burgan, with over fifty years of production, much of the field development occurred before modern diagnostic logging tools became available. Therefore, direct correlation of core lithologies and corresponding lithofacies description to multilog character is not possible in the majority of wells. Relationships discovered between shale volume (V_SH) ranges and effective porosity (#PHI#eff) to permeability transforms allowed us to apply unique rock properties to flow units or "facies" defined by the V_SH-porosity ranges. These flow facies eliminated the difficult task of trying to predict changing lithologies and lithofacies in wells with limited log traces and no core.