Method for initiating in situ combustion within a subterranean formation

Claim 1

A METHOD FOR INITIATING IN SITU COMBUSTION WITHIN A PERMEABLE PETROLEUM-CONTAINING SUBTERANEAN FORMATION PENETRATED BY AN NJECTION WELL HAVING AT LEAST TWO CONDUIT MEANS FOR CONVEYING FLUIDS FROM THE EARTH''S SURFACE TO SAID FORMATION TO BE IGNITED, THE STEPS COMPRISING: (A) INJECTING STEAM THROUGH ONE OF SAID CONDUIT MEANS INTO SAID FORMATION TO BE IGNITED, SAID STEAM BEING AT SUITABLE CONDITONS OF TEMPERATURE AND PRESSURE TO HEAT THE WELL-EXPOSED FACE OF SAID FORMATION TO AT LEAST 300*F., AND DURING AT LEAST TERMINAL STEAM INJECTION SAID CONDUIT MEANS BEING RESTRICTED TO FLOWS OF OXYGEN-CONTAINING GAS INTO THE WELL; (B) INTRODUCING INTO ONE OF SAID CONDUIT MEANS A QUANTITY OF LINSEED OL SUFFICIENT TO WET THE FACE OF THE FORMATION TO BE IGNITED WHILE INTERRUPTING THE FLOW OF OTHER FLUIDS INTO THE FORMATION THROUGH SAID CONDUIT MEANS; (C) PASSING STEAM THROUGH SAID CONDUIT MEANS RECEIVING LINSEED OIL IN A FLOW SUFFICIENT ONLY TO DISPLACE THE LINSEED OIL INTO THE FACE OF SAID FORMATION BUT NOT TO DRIVE SAID LINSEED OIL INTO THE FORMATION AWAY FROM THE WELL, AND WHILE THE STEAM YET FLOWS INTO THE WELL; (D) INJECTING A GASEOUS STREAM CONTAINING FREE OXYGEN THROUGH OTHER OF SAID CONDUIT MEANS WHICH HAVE NOT CARRIED LINSEED OIL INTO THE FORMATIONIN AN AMOUNT SUFFICIENT TO SUPPORT COMBUSION WHEREBY THE LINSEED OIL SPONTANEOUSLY IGNITES AT THE HEATED FACE OF THE FORMATION AND THE RESULTING COMBUSTION FRONT THEREBY MOVES ONLY RADIALLY OUTWARDLY FROM THE WELL INTO THE FORMATION; AND

Claim 2

A METHOD FOR INITIATING IN SITU COMBUSTION WITHIN A PERMEABLE PETROLEUM-CONTAINING SUBTERANEAN FORMATION PENETRATED BY AN NJECTION WELL HAVING AT LEAST TWO CONDUIT MEANS FOR CONVEYING FLUIDS FROM THE EARTH''S SURFACE TO SAID FORMATION TO BE IGNITED, THE STEPS COMPRISING: (A) INJECTING STEAM THROUGH ONE OF SAID CONDUIT MEANS INTO SAID FORMATION TO BE IGNITED, SAID STEAM BEING AT SUITABLE CONDITONS OF TEMPERATURE AND PRESSURE TO HEAT THE WELL-EXPOSED FACE OF SAID FORMATION TO AT LEAST 300*F., AND DURING AT LEAST TERMINAL STEAM INJECTION SAID CONDUIT MEANS BEING RESTRICTED TO FLOWS OF OXYGEN-CONTAINING GAS INTO THE WELL; (B) INTRODUCING INTO ONE OF SAID CONDUIT MEANS A QUANTITY OF LINSEED OL SUFFICIENT TO WET THE FACE OF THE FORMATION TO BE IGNITED WHILE INTERRUPTING THE FLOW OF OTHER FLUIDS INTO THE FORMATION THROUGH SAID CONDUIT MEANS; (C) PASSING STEAM THROUGH SAID CONDUIT MEANS RECEIVING LINSEED OIL IN A FLOW SUFFICIENT ONLY TO DISPLACE THE LINSEED OIL INTO THE FACE OF SAID FORMATION BUT NOT TO DRIVE SAID LINSEED OIL INTO THE FORMATION AWAY FROM THE WELL, AND WHILE THE STEAM YET FLOWS INTO THE WELL; (D) INJECTING A GASEOUS STREAM CONTAINING FREE OXYGEN THROUGH OTHER OF SAID CONDUIT MEANS WHICH HAVE NOT CARRIED LINSEED OIL INTO THE FORMATIONIN AN AMOUNT SUFFICIENT TO SUPPORT COMBUSION WHEREBY THE LINSEED OIL SPONTANEOUSLY IGNITES AT THE HEATED FACE OF THE FORMATION AND THE RESULTING COMBUSTION FRONT THEREBY MOVES ONLY RADIALLY OUTWARDLY FROM THE WELL INTO THE FORMATION; AND