Developing Concepts for Excess Permeability in the Pre-Salt: Dynamic Modeling to Evaluate Impacts of Excess Permeability (Non-Matrix) Scenarios on Reservoir Performance

Summary Reservoir scenarios, generated from multiscale data for Non-Matrix across a variety of static and dynamic data types in the Pre-Salt carbonates, are integrated into 3D cross-sectional reservoir model. These scenarios include different geological concepts of matrix and non-matrix types through Single Porosity/Single Permeability (SPSP) and Dual Porosity/Dual Permeability (DPDP) models. Different fluid types ranging from heavy to light hydrocarbon, column heights, and displacement functions are tested. Compositional flow simulations are run to quantify the impact of these scenarios and test the sensitivity to recovery, well rate, water and gas arrivals using primary depletion and secondary recovery of water, gas reinjection, and a combination of both. Moreover, scenarios for miscible CO2 injections are conducted to learn variable impacts on production and reservoir performance. The study produced credible scenarios with an impact on appraisal and development decisions (Estimated Ultimate Recovery/ EUR basis) for CO2-rich gas cap or high CO2 oil outcomes. It also provides guidance, thresholds, and scenarios to support business decision-making when CO2 is encountered including Gas-cap development feasibility and gas management.