Recovery of oil from partially depleted reservoirs by secondary recovery

Claim 1

IN A SECONDARY RECOVERY PROCESS EMPLOYING A WATER DRIVE TO FACILITATE THE DRAINAGE OF RESIDUAL PETROLEUM OIL FROM A PARTIALLY DEPLETED, SUBTERRANEAN OIL-BEARING NORMALLY WATER-WETTABLE RESERVOIR, TRAVERSED BY A WATER INJECTION WELL AND A RECOVERY WELL, A METHOD FOR MINIMIZING THE RESISTANCE OF SAID RESERVOIR TO THE FLOW OF SAID WATER DRIVE THROUGH A CIRCUMAMBIENT ZONE IMMEDIATELY ADJACENT SAID INJECTION WELL WHICH COMPRISES FORCING INTO SAID RESERVOIR THROUGH SAID INJECTION WELL AN AQUEOUS SOLUTION CONTAINING ABOUT 0.1-10% BY WEIGHT OF A WATER-SOLUBLE METAL SALT OF AN ORGANIC SILICONIC ACID INTO A CIRCUMAMBIENT ZONE IMMEDIATELY ADJACENT THE INJECTION BORE HOLE AND HAVING A RADIUS NOT GREATER THAN ABOUT 20 FEET, IN A VOLUME EQUAL TO ABOUT 25-75% OF SAID ZONE, CONTACTING THE AQUEOUS SALT-CONTAINING SOLUTION WHILE IN SAID CIRCUMAMBIENT ZONE WITH AN ACIDIC SOLUTION WHEREBY A SILICONE POLYMER IS PRECIPITATED TO FORM AN OIL-WETTABLE COATING ON THE MINERAL SURFACES OF SAID CIRCUMAMBIENT ZONE WITHOUT DELETERIOUSLY AFFECTING THE SPECIFIC PERMEABILITY OF SAID ZONE, AND INJECTING A WATER INJECTION FLUID INTO SAID RESERVOIR THROUGH SAID ZONE TO FORCE SAID RESIDUAL OIL THEREFROM.