A method for recovering low gravity viscous crude oil or bitumen from a subterranean formation comprising first injecting super heated steam, next initiating an in situ combustion by injecting air, followed by an in situ combustion wherein both super heated steam and air are injected, then simultaneously performing an in situ combustion by injecting air while also injecting water and finally injecting water.

A method for recovering viscous oil from a subterranean formation through a wellbore having a horizontal section into the formation. Steam is circulated through the horizontal section to initially heat the formation and to produce fluids to the surface. After the initial heating is complete, production is ceased while the injection of steam is continued to accumulate a slug of steam within and around the horizontal section. The well is then shut-in and the formation is allowed to "soak". Product...

Disclosed is a gravity-drainage assisted steam flooding process for the recovery of all from thin viscous heavy oil reservoirs using a single horizontal wellbore. Steam is injected through a fully or partially insulated tubing to exit at or near the toe of a long horizontal well penetrating a viscous oil reservoir. Initially, low (10-30%) quality steam is circulated along the well to condition the wellbore and increase the heated radius to about 1 or 2 meters. Oil and reservoir fluids immediatel...

In a "huff and puff" type steam stimulation process for enhancing the recovery of oil from an underground formation, amounts of caustic material such as sodium hydroxide are added to the steam in concentrations greater than 500 parts per million, resulting in further enhancement of recovery.

Hydrocarbon products from viscous tar sands are recovered by continuously injecting a hot solvent containing relatively large amounts of aromatics into the formation. Alternatively, steam and solvent are cyclically and continuously injected into the formation to recover the values. The last stimulation is by steam so that solvent is recovered. A third alternative is to continuously inject a mixture of steam and solvent vapors and liquid into the formation. In all cases, the solvent, except perha...

A method for recovering oil by injecting a miscible fluid to drive the oil vertically downward to the producing wells wherein the injected miscible fluid is heated so that it has a temperature equal to or greater than normal reservoir fluid temperature.

A method for the in-situ recovery of viscous oils or bitumen from subterranean oil-bearing formations by the injection of steam or a mixture of steam and an oxygen-containing gas under operating conditions that utilize pressurization and drawdown cycles wherein carbon dioxide is injected at the start of the pressurization cycle.

A method of increasing the near-wellbore permeability of porous formation comprises exposing formation to an elevated temperature of 400.degree. C. or greater to cause dehydration of the clay lattices, vaporization of any blocked water, mud filtrate or other fluids, and/or destruction of the clay structure.

A method for lowering the viscosity of a heavy hydrocarbon in situ in a well formation so as to improve well production wherein the heavy hydrocarbon has an API gravity in the range between 6.degree. and 12.degree. and a dynamic viscosity in the range between 300 and 900 centipoises @ 195.degree. F. comprising lowering the viscosity of a virgin heavy hydrocarbon outside of a well formation wherein said heavy hydrocarbon has an API gravity in the range between 6 and 12 degrees and a dynamic visco...

A method for recovery of oil from a subterranean, viscous oil-containing formation penetrated by one or more wells each of which is provided with at least one separate flow paths, the first flow path in fluid communication with the bottom of the formation from adjacent or below the formation and the second flow path in fluid communication with substantially the full vertical thickness of the formation. Steam is injected into the formation via the second flow path and fluids including oils are re...