Advances In Complex Reservoir Evaluation Based on Geophysical Well Logs


W. H. Fertl, A. K. Sinha, Western Atlas International



The Complex Reservoir Analysis (CRA) computes lithology (such as shale and mineral volumes), porosity, water saturation, and relative permeabilities in formations with interbedded limestone, dolomite, anhydrite, etc. Porosity options include crossplot and individual log response techniques. Corrections for light hydrocarbons are applied. In solving for porosity and mineral volumes, sand, limestone, dolomite, and anhydrite lines are defined on either density/neutron or neutron/acoustic crossplots. Furthermore four additional mineral lines can be specified on these crossplot charts. Water saturations may be calculated via six different saturation models.