Dynamic Rock Typing Study and Application of Complex Carbonate Reservoir in Middle East

Carbonate reservoirs have complex depositional environment, Lithofacies and geological properties in Middle East. One saturation function to describe and characterize initial fluid saturation distribution and fluid movement cannot meet the needs of simulation and production forecast. The study classify reservoirs into five static rock typing by Lithofacies, petrology, mineralogy, Diagenesis study. Each RRT has a typical and unique set of porosity/permeability, saturation height function and pore throat Size Distribution. This study deduces mathematical correlation between saturation endpoints and relative permeability at given a end point by SCAL analysis. A relative permeability curve is obtained for each RRT. Capillary Pressure curves were established by J Function from MICP for each RRT. The dynamic saturation model was consistent with static saturation model. To lower saturation function uncertainties’ impacts on production forecast, endpoint and relative permeability curves shape are considered in sensitivity and uncertainty analysis. The study indicates (1) The challenge in contradiction between insufficient SCAL data and complex fluids movement is solved; (2) During approach, DRRT assign relative permeability curves and capillary curves to each cell; (3) Dynamic water saturation reflect complicated geology /petrophysical property variation.