Fracturing liquid and method of use thereof in treating wells

Claim 1

IN A METHOD OF FRACTURING A FLUID-BEARING EARTH FORMATION PENETRATED BY A WELL BY INJECTING INTO THE WALL AN ACIDIC FRACTURING LIQUID SELECTED FROM THE CLASS CONSISTING OF AN AQUEOUS SOLUTION OF HYDROCHLORIC ACID AND AN EMULSION OF AN OIL AND AQUEOUS HYDROCHLORIC ACID, THE IMPROVEMENT CONSISTING ESSENTIALLY OF SUSPENDING SAID ACIDIC FRACTURING LIQUID AN ALKALINE-SOLUBLE IN SSID LIQUID TO SOUBLE LIGNIN WHICH IS INSOUBLE IN SAID ACID LIQUID TO MAKE A SLURRY, INJECTING THE SLURRY INTO THE FORMATIOD UNDER PRESSURE SO THAT THE SLURRY IS FORCED INTO THE MORE EXPOSED FISSURES AND RECESSES TO FORM A FILTER CAKE THEREIN TO PREVENT EXCESSIVE LOSS OF SAID LIQUID, CONTINUING THE PRESURE TO CAUSE FURTHER PENETRATION OF THE LESS EXPOSED FISSURES AND RECESSES IN TIGHTER PORTIONS OF SAID FORMATION, FRACTURING THE FORMATION CAUSING SAID SLURRY TO RAISE ITS PH VAULE TO EFFECT DISSOLUTION OF THE LIGNIN AND FORM A SOLUTION THEREOF, ADDING AN OIL TO THE WELL TO FORCE THE RESULTING SOLUTION BACK INTO THE MORE REMOTE PORTIONS OF THE FORMATION, AND RELEASING THE PRESSURE ON THE WELL.