| abstract |
A process for removing residual oil from the near wellbore area of a subterranean formation adjacent an injection well of a waterflood operation to improve water injectivity comprising injection through said well into said area seawater containing a surfactant having the formula: RO(C3H6O)7(C2H4O)2YX wherein: R is a mixture of alkyl groups containing from 12 to 15 carbon atoms, Y is sulfate group, and X is a monovalent cation. After the treatment to improve water injectivity, the formation is waterflooded. |