Conventional geologic modeling in the highly heterogeneous Hayat/Yasser field was not adequate to capture the heterogeneity and address the objectives of a held study. Geostatistics were used to develop a reservoir model with 30 layers that adequately captured the vertical heterogeneity of the lower Bahariya reservoir. Geostatistics were used to investigate alternative models. A very fine model with 200 layers did not provide additional details relevant to fluid now compared with a 30-layer model that was more appropriate for reservoir simulation.