RECOVERY OF PETROLEUM FROM VISCOUS PETROLEUM-CONTAINING FORMATIONS INCLUDING TAR SANDS

摘要

ABSTRACT OF THE DISCLOSUREA method for the in-situ recovery of low APIgravity oils or bitumen from subterranean hydrocarbon-bearingformations wherein the recovery is optimized by the injectionof a mixture of an oxygen-containing gas and steam until therecovery efficiency declines, followed by the injection ofa mixture of light hydrocarbon and steam, under operatingconditions that may utilize pressurization and drawdown cycles.