Department of Petroleum Engineering, University Technology Malaysia
In thin-layered reservoirs, drilling engineers face tough challenges—planning their drilling programs to follow the most productive reservoir layers while avoiding nearby water, gas or high-pressure zones. The rewards for a successful drilling strategy are clear—increased oil production and reduced water cut. In an oil field in the Persian Gulf, for example, oil production was increased four- to six fold and water cut was reduced by one-third using the latest formation modeling and geosteering techniques. Until recently, drilling thin layers was extremely difficult. Traditional geometrical drilling trajectories were unable to match the subtle variations in layer dip and depth, so many wells left the target zone and encountered watered-out layers. This paper has implemented modern geosteering methods to give drillers much greater control and help change the way operators develop thin-layered oil reservoirs, enabling them to increase hydrocarbon recovery and reduce water cut.