Treating formations with solid forming liquids

Claim 1

THE METHOD OF SELECTIVELY PLUGGING A NON-OIL-PRO DUCING ZONE OF AN OIL-PRODUCING FORMATION PENETRATED BY A WELL, COMPRISING INJECTING INTO SAID FORMATION AN EMULSION CONSISTING ESSENTIALLY OF WATER AND OIL-SOLUBLE, WATER-INSOLUBLE PLUGGING AGENT NON-REACTIVE WITH SAID FORMATION, SAID EMULSION BEING AT A TEMPERATURE ABOVE THE FREEZING POINT OF SAID PLUGGING AGENT AT FORMATION PRESSURE AND SAID FREEZING POINT OF SAID PLUGGING AGENT BEING ABOVE FORMATION TEMPERATURE, WHEREBY SAID PLUGING AGENT ENTERS SAID FORMATION AS A LIQUID BUT FREEZES TO A SOLID STATE UPON COOLING TO FORMATION TEMPERATURE, AT LEAST 65 PERCENT OF THE VOLUME OF SAID EMULSION BEING WATER, WHEREBY THE FORMATION RETAINS SOME OF ITS PERMEABILITY SO THAT OIL FLOWING THROUGH ANY OIL-PRODUCING ZONE, WHEN THE WELL IS PRODUCED, DISSOLVES THE RESULTING SOLIDIFIED PLUGGING AGENT IN SAID OIL-PRODUCING ZONE, THUS REDTORING THE ORIGINAL PERMEABILITY OF THE LATTER WHILE LEAVING THE NON-OIL-PRODUCING ZONE PARTIALLY PLUGGED.

Claim 2

THE METHOD OF SELECTIVELY PLUGGING A NON-OIL-PRO DUCING ZONE OF AN OIL-PRODUCING FORMATION PENETRATED BY A WELL, COMPRISING INJECTING INTO SAID FORMATION AN EMULSION CONSISTING ESSENTIALLY OF WATER AND OIL-SOLUBLE, WATER-INSOLUBLE PLUGGING AGENT NON-REACTIVE WITH SAID FORMATION, SAID EMULSION BEING AT A TEMPERATURE ABOVE THE FREEZING POINT OF SAID PLUGGING AGENT AT FORMATION PRESSURE AND SAID FREEZING POINT OF SAID PLUGGING AGENT BEING ABOVE FORMATION TEMPERATURE, WHEREBY SAID PLUGING AGENT ENTERS SAID FORMATION AS A LIQUID BUT FREEZES TO A SOLID STATE UPON COOLING TO FORMATION TEMPERATURE, AT LEAST 65 PERCENT OF THE VOLUME OF SAID EMULSION BEING WATER, WHEREBY THE FORMATION RETAINS SOME OF ITS PERMEABILITY SO THAT OIL FLOWING THROUGH ANY OIL-PRODUCING ZONE, WHEN THE WELL IS PRODUCED, DISSOLVES THE RESULTING SOLIDIFIED PLUGGING AGENT IN SAID OIL-PRODUCING ZONE, THUS REDTORING THE ORIGINAL PERMEABILITY OF THE LATTER WHILE LEAVING THE NON-OIL-PRODUCING ZONE PARTIALLY PLUGGED.