Details
Gulf of Thailand
Well type
Horizontal oil wells
Challenge
High water cut
Low oil mobility
Background
An oil field offshore Thailand is characterized by complex reservoir geometries (comprising multiple sand pockets with intermittent shale) and broad heterogeneity. Relatively-higher-mobility water encroaching on viscous oil, combined with strong, active aquifer support, was causing early water breakthrough in horizontal wells, sometimes within days of commencing production. In some wells, the water cut increased exponentially, leading to oil recovery of less than 10%.
Choking the rate of production at surface to control water cut impacted production targets negatively, and downhole treatment was not a viable option because it could cause formation damage. Inflow control devices (ICDs) were proposed as a potential solution for Well A. The performance of this well would be compared with the offset Well B completed in the same sand using conventional stand-alone screens.