Determination of residual oil in a formation

Claim 1

A METHOD FOR DETERMINING THE RESIDUAL OIL IN AN OIL BEARING FORMATION PENETRATED BY THE BORE HOLE OF A WELL COMPRISING THE STEPS OF: A. LOGGING SAID FORMATION WITH A RADIOACTIVE DETECTION MEANS TO OBTAIN LOGGING DATA MEASUREMENTS OF THE NATURAL OCCURING RADIOACTIVITY OF SAID FORMATION, B. INJECTING INTO SAIDFORMATION, THROUGH THE BORE HOLE OF SAID WELL, IN AQUEOUS SOLUTION CONTAINING WATER-SOLUBLE RADIOACTIVE CONTAMINANTS SAID WATER-SOLUBLE RADIOACTIVE CONTAMINANTS BEING PRESENT IN AN AMOUNT SUFFICIENT TO PROVIDE FROM ABOUT 5 X 10**2 TO ABOUT 5 MICROCURRIES/CC OF RADIOACTIVITY IN SAID AQUEOUS SOLUTION, C. LOGGING SAID FORMATION FOR A SECOND TIME WITH RADIOACTIVE DETECTION MEANS TO OBTAIN SECOND LOGGING DATA MEASUREMENTS OF SAID FORMATION, SUCH MEASUREMENTS BEING INDICATIVE OF THE RELATIVE QUANTITIES OF RESIDUAL OIL ANDFORMATION WATERS PRESENT IN SAID FORMATION, D. INJECTING INTO SAID FORMATION THROUGH THE BORE HOLE OF SAID WELL, A SUFFICIENT AMOUNT OF AN OIL MISCIBLE SOLUTION TO DISPLACE SUBSTANTIALLY ALL OF THE RESIDUAL OIL IN THE FORMATION SURROUNDING THE BORE HOLE, E. INJECTING INTO SAID FORMATION, THROUGH THE BORE HOLE OF SAID WELL, A SUFFICIENT AMOUNT OF WATER TO DISPLACE SUBSTANTIALLY ALL OF THE OIL MISCIBLE SOLUTION IN SAID FORMATION THEREBY RENDERING SAME SUBSTANTIALLY 100 PERCENT WATER SATURATED, F. LOGGING SAID FORMATION FOR A THIRD TIME TO OBTAIN LOGGING DATA MEASUREMENTS, WHICH WHEN COMPARED WITH SAID FIRST AND SECOND LOGGING DATA MEASUREMENTS, IN COMBINATION WITH THE KNOWN POROSITY OF SAID FORMATION AND THE CONCENTRATION OF RADIOACTIVE CONTAMINANTS EMPLOYED, INDICATES THE AMOUNT OF RESIDUAL OIL PRESENT IN SAID FORMATION, AND, G. COMPARING THE LOGGING DATA OF NA) THE LOGGING DATE OF NC) AND THE LOGGING DATA OF (F) TO DETERMINE THE AMOUNT OF SAID RESIDUAL OIL PRESENT IN SAID OIL BEARING FORMATION.

Claim 2

A METHOD FOR DETERMINING THE RESIDUAL OIL IN AN OIL BEARING FORMATION PENETRATED BY THE BORE HOLE OF A WELL COMPRISING THE STEPS OF: A. LOGGING SAID FORMATION WITH A RADIOACTIVE DETECTION MEANS TO OBTAIN LOGGING DATA MEASUREMENTS OF THE NATURAL OCCURING RADIOACTIVITY OF SAID FORMATION, B. INJECTING INTO SAIDFORMATION, THROUGH THE BORE HOLE OF SAID WELL, IN AQUEOUS SOLUTION CONTAINING WATER-SOLUBLE RADIOACTIVE CONTAMINANTS SAID WATER-SOLUBLE RADIOACTIVE CONTAMINANTS BEING PRESENT IN AN AMOUNT SUFFICIENT TO PROVIDE FROM ABOUT 5 X 10**2 TO ABOUT 5 MICROCURRIES/CC OF RADIOACTIVITY IN SAID AQUEOUS SOLUTION, C. LOGGING SAID FORMATION FOR A SECOND TIME WITH RADIOACTIVE DETECTION MEANS TO OBTAIN SECOND LOGGING DATA MEASUREMENTS OF SAID FORMATION, SUCH MEASUREMENTS BEING INDICATIVE OF THE RELATIVE QUANTITIES OF RESIDUAL OIL ANDFORMATION WATERS PRESENT IN SAID FORMATION, D. INJECTING INTO SAID FORMATION THROUGH THE BORE HOLE OF SAID WELL, A SUFFICIENT AMOUNT OF AN OIL MISCIBLE SOLUTION TO DISPLACE SUBSTANTIALLY ALL OF THE RESIDUAL OIL IN THE FORMATION SURROUNDING THE BORE HOLE, E. INJECTING INTO SAID FORMATION, THROUGH THE BORE HOLE OF SAID WELL, A SUFFICIENT AMOUNT OF WATER TO DISPLACE SUBSTANTIALLY ALL OF THE OIL MISCIBLE SOLUTION IN SAID FORMATION THEREBY RENDERING SAME SUBSTANTIALLY 100 PERCENT WATER SATURATED, F. LOGGING SAID FORMATION FOR A THIRD TIME TO OBTAIN LOGGING DATA MEASUREMENTS, WHICH WHEN COMPARED WITH SAID FIRST AND SECOND LOGGING DATA MEASUREMENTS, IN COMBINATION WITH THE KNOWN POROSITY OF SAID FORMATION AND THE CONCENTRATION OF RADIOACTIVE CONTAMINANTS EMPLOYED, INDICATES THE AMOUNT OF RESIDUAL OIL PRESENT IN SAID FORMATION, AND, G. COMPARING THE LOGGING DATA OF NA) THE LOGGING DATE OF NC) AND THE LOGGING DATA OF (F) TO DETERMINE THE AMOUNT OF SAID RESIDUAL OIL PRESENT IN SAID OIL BEARING FORMATION.