THE USE OF PORE SCALE MODELING TO PREDICT RESERVOIR PARAMETERS FROM DRILL CUTTINGS

摘要

This work investigates the use of an integrated pore-scale modeling procedure to determine reservoir rock parameters from drill cuttings. Our approach is based on reconstructing digital 3D models of reservoir rocks with input data obtained from drill cuttings. A variety of cuttings were investigated, ranging from chips several millimeters in size produced by conventional drill bits to a mixture of disintegrated sand grains and drilling mud produced by modern PDC drill bits. Different sample preparation methods were employed to analyze and extract petrographical information (porosity, mineralogy, and grain sizes) from the cuttings. Data derived from thin section analysis was supplemented by X-ray diffraction analysis (XRD), sieving and porosity logs. This information was used as input to a process based reconstruction algorithm to generate 3D models of the rock microstructure. Effective properties that are numerically calculated directly from the reconstructed models are absolute permeability, electrical resistivity, NMR relaxation, and elastic moduli. Relative permeability and capillary pressure curves are calculated on the pore network representations of the reconstructed rocks. Where data are available, computed properties are compared with data from well logs and laboratory measurements. In conclusion, this study shows that integrated pore-scale modeling offers exciting possibilities for estimating reservoir rock properties from drill cuttings.