Selective treatment of geological formations

Claim 1

IN THE TREATMENT OF A GEOLOGICAL FORMATION CONTAINING RANDOM STREAKS VARYING IN PERMEABILITY EACH TO THE OTHER, A PROCESS FOR ISOLATING THE MORE PERMEABLE STREAKS OF A GEOLOGICAL FORMATION TRAVERSED BY A BORE HOLE FROM THE LESS PERMEABLE STREAKS, WHICH COMPRISES FORCING INTO SAID FORMATION A HEATED, LIQUID HEAT-TRANSFER MEDIUM WHEREBY SAID FORMATION IS HEATED TO A TEMPERATURE OF NOT LESS THAN ABOUT 20*F. IN EXCESS OF NORMAL FORMATION TEMPERATURES, INTRODUCING IN SAID FORMATION A COLLODIAL SOL WHICH WILL FORM, AT THE ELEVATED TEMPERATURE PRODUCED IN THE FORMATION, A THERMAL-REVERSIBLE GEL SOLATABLE UPON COOLING, WHEREBY SAID SOL IS GELATED WITHIN SAID FORMATION ALLOWING SAID FORMATION TO COOL FOR A TIME SUFFICIENT FOR THE TEMPERATURE IN THE LESS PERMEABLE STREAKS TO REVERT TO A TEMPERATURE SUBSTANTIALLY BELOW THE TEMPERATURE IN SAID MORE PERMEABLE STREAKS, WHEREBY SAID SOL WILL REMAIN GELATED IN THE SAID MORE PERMABLE STREAKS BUT WILL PEPTIZE IN SAID LESS PERMEABLE STREAKS, AND FORCING INTO SAID UNSEALED, LESS PERMABLE STREAKS AN ACIDIZING AGENT CAPABLE OF REACTING WITH SAID FORMATION IN AN AMOUNT SUFFICIENT TO REDUCE THE RESISTANCE OF SAID FORMATION TO THE FLOW OF FLUIDS THERETHROUGH.