This paper presents the results of a 4.2 million cells simulation model for the Shaybah field in Saudi Arabia. This model was a follow up to a previous model that was used to scope the initial development of the field. Since then, many wells were drilled, the facies templates were updated and the relative permeability curves were refined. This model has had a significant impact on optimizing the production strategy of the Shaybah field including designing and locating newly drilled multi-lateral and smart wells.
Reservoir simulation was used extensively during the development stage of the field and is being used continuously to assess different production strategies, and to optimize well placement and completions. Since the field first came on stream more than seven years ago, a comprehensive data acquisition program was initiated and a new geological model was built which in turn led to building a new simulation model. During the process of field development and the simulation update, the importance of several components of the model became more apparent. Such components were the facies templates, the interfacial tension and contact angles and the shape of the relative permeability curves for the various rock types.
The impact of improved facies templates resulted in better permeability model and in turn in better pressure match; the impact of the gas/oil relative permeability curves refinement was seen in an improvement in the gas oil ratio match and the impact of the interfacial tension and contact angle resulted in improving the initial water movement.
The Shaybah field, discovered in 1968, in the Rub' Al-Khali desert of Saudi Arabia, is approximately 13 km (8 miles) wide and 64 km (40 miles) long. The surface terrain is comprised of salt flat areas known as Sabkahs and mountainous sand dunes (up to 200 meters high).