Quantification of reservoir connectivity for reservoir description applications

This study investigates means for indirectly incorporating dynamic production data constraints into geostatistically-derived reservoir descriptions. Simulated primary and waterflood performance for two-dimensional vertical, three-phase, black oil reservoir systems are used to identify and quantify spatial characteristics which control well performance. The paper focuses on the development of reservoir connectivity parameters and the estimation of well performance characteristics based on this parameter. This approach is considered to be an indirect method because the reservoir connectivity parameter is computed from static spatial reservoir properties rather than from dynamic production data, thus simplifying the process of obtaining a realistic reservoir description. The reservoir connectivity parameter was found to correlate strongly with : (1) secondary recovery efficiency, (2) drainable hydrocarbon pore volume and (3) floodable hydrocarbon pore volume. Mobility ratio sensitivities show that, given a reservoir description, the water breakthrough time can be estimated using the reservoir connectivity parameter. This can be achieved using 3-5 orders of magnitude less computational time than required for comparable flow simulations.