Carbonated waterflooding for viscous oil recovery

摘要

Viscous oil is recovered from a subterranean, viscous oil- containing formation by injecting a slug of CO.sub.2 carbonated water containing a CO.sub.2 solubility promoter into the formation via an injection well, subsequently injecting a heated fluid to release the CO. sub.2 from the injected carbonated water and recovering oil from the formation through a production well.