Reservoir characterization is the most important input element in building a robust geological and simulation models. The Improvement in reservoir description enhances the understanding of the reservoir heterogeneity and reduces the uncertainties on field development. This can be achieved with better characterisation of reservoir properties such as Rock Types, porosity, permeability and saturation. The reservoir is developed by water and gas injection. In order to better understand field behavior, enhance oil recovery, produce difficult oil, a detailed reservoir characterization study was performed, followed by construction of fine grid geological model and simulation model. The main goal of the model is to predict middle and long term development plan. The depositional model represents a shallow water carbonate platform with a set of facies that characterize each system tract. These facies range from bioclastic Wackestone, Mudstones, with sponge Spicules of shallow shelf through a shoal area with Peloidal and Oolitic grain dominated fabrics to the restricted lagoon foraminifera bioturbated Wackestone and microcrystalline dolomite and finally into the upper intertidal facies of macro crystalline dolomite and nodular anhydrite. The digenetic model comprised surface, subtidal, shallow, and deep burial diagenetic events, such as micritization, fringing calcite marine cement, vadose grain leaching, compaction, stylolitization, dolomitisation, anhydrite cementation and fracturing.