Abstract: Bitumen is recovered from a subterranean formation of heavy oil sands traversed by at least one injection well and at least one associated production well in fluid communication with each injection well. Air in admixture with a heating fluid selected from the group consisting of low quality steam, hot water, or mixtures thereof, and an alkalinity agent are injected into the formation by way of each injection well. The subterranean heavy oil sands are thereby raised to a temperature in the range of about 200.degree. to 350.degree. F. A portion of the bitumen at reduced viscosity is oxidized without burning to produce additional petroleum acids which are neutralized to form emulsifying agents. The condensed steam and/or hot water contacting the bitumen form with it a bitumen-water emulsion. By pressure from the injected mixture of air and heating fluid, the resulting bitumen-water emulsion is then recovered from each production well.

Abstract: A method for the in-situ recovery of low API gravity oils or bitumen from subterranean hydrocarbon-bearing formations wherein the recovery is optimized by the injection of a mixture of an oxygen-containing gas and steam until the recovery efficiency declines, followed by the injection of a mixture of light hydrocarbon and steam, under operating conditions that may utilize pressurization and drawdown cycles.