Method and means for locating subsoil formations during drilling

Claim 2

IN THE LOGGING OF SUBTERRANEAN FORMATIONS PENETRATED IN HOLE DRILLING OPERATIONS BY ANALYZING THE OXIDATION-REDUCTION POTENTIAL OF THE DRILLING MUD FLUID CONTINUOUSLY CIRCULATED THROUGH THE DRILLED HOLE, THE METHOD OF DETERMINING VARIATIONS OF THE REDOX POTENTIAL INDUCED IN SAID MUD BY THE CONTACT OF THE MUD WITH THE DRILLED PARTICLES, COMPRISING THE STEPS OF: CONTINUOUSLY ADJUSTING THE REDOX POTENTIAL OF THE MUD TO A PREDETERMINED REDOX VALUE BY ADDING A SUITABLE REAGENT TO SAID MUD BEFORE CIRCULATING IT THROUGH THE HOLE; CONTINUOUSLY MEASURING SAID ADJUSTED REDOX POTENTIAL OF THE MUD; CIRCULATING THE MUD THROUGH THE HOLE; CONTINUOUSLY MEASURING THE REDOX POTENTIAL OF THE MUD EFFLUENT FROM THE HOLE, AND COMPARING THE SAID REDOX MEASUREMENTS MADE ON THE SAME MUD PORTIONS.

Claim 3

IN A HOLE DRILLING EQUIPMENT O THE TYPE THAT INCLUDES A ROTARY DRILLING RIG, CONDUIT MEANS FOR CIRCULATING DRILLING FLUID THROUGH SAID DRILLING RIG TO THE BOTTOM OF A BORE HOLE, A MUD RETURN LINE FOR RETURNING DRILLING FLUID FROM THE BORE SPACE SURROUNDING SAID DRILLING RIG TO THE EARTH''S SURFACE, A MUD PIT AT THE SURFACE CONNECTED TO SAID MUD RETURN LINE AND ACTING AS A TANK, AND PUMPING MEANS FOR CONTINUOUSLY CIRCULATING SAID DRILLING MUD FLUID FROM SAID PIT DOWN THROUGH SAID CONDUIT MEANS AND UP THROUGH THE HOLE BORE SURROUNDING THE DRILL RIG AND THROUGH SAID MUD RETURN LINE BACK INTO SAID PIT, THEIMPROVED LOGGING DEVICE COMPRISING A FIRST REDOX-POTENTIAL MEASURING REVERSIBLE ELECTRODE EXTENDING INTO SAID MUD RETURN LINE FOR CONTACT WITH THE MUD EFFLUENT FLOWING THERETHROUGH, A SECOND REDOX POTENTIAL-MEASURING REVERSIBLE ELECTRODE EXTENDING INTO SAID MUD PIT FOR CONTACT WITH THE MUD CONTAINED THEREIN, A REDOX POTENTIAL-MEASURING INSTRUMENT, AND ELECTRICALLY INSULATED WIRES ELECTRICALLY CONNECTING SAID FIRST AND SECOND REVERSIBLE ELECTRODES TO SAID REDOX POTENTIAL MEASURING INSTRUMENT.

Claim 4

IN A HOLE DRILLING EQUIPMENT O THE TYPE THAT INCLUDES A ROTARY DRILLING RIG, CONDUIT MEANS FOR CIRCULATING DRILLING FLUID THROUGH SAID DRILLING RIG TO THE BOTTOM OF A BORE HOLE, A MUD RETURN LINE FOR RETURNING DRILLING FLUID FROM THE BORE SPACE SURROUNDING SAID DRILLING RIG TO THE EARTH''S SURFACE, A MUD PIT AT THE SURFACE CONNECTED TO SAID MUD RETURN LINE AND ACTING AS A TANK, AND PUMPING MEANS FOR CONTINUOUSLY CIRCULATING SAID DRILLING MUD FLUID FROM SAID PIT DOWN THROUGH SAID CONDUIT MEANS AND UP THROUGH THE HOLE BORE SURROUNDING THE DRILL RIG AND THROUGH SAID MUD RETURN LINE BACK INTO SAID PIT, THEIMPROVED LOGGING DEVICE COMPRISING A FIRST REDOX-POTENTIAL MEASURING REVERSIBLE ELECTRODE EXTENDING INTO SAID MUD RETURN LINE FOR CONTACT WITH THE MUD EFFLUENT FLOWING THERETHROUGH, A SECOND REDOX POTENTIAL-MEASURING REVERSIBLE ELECTRODE EXTENDING INTO SAID MUD PIT FOR CONTACT WITH THE MUD CONTAINED THEREIN, A REDOX POTENTIAL-MEASURING INSTRUMENT, AND ELECTRICALLY INSULATED WIRES ELECTRICALLY CONNECTING SAID FIRST AND SECOND REVERSIBLE ELECTRODES TO SAID REDOX POTENTIAL MEASURING INSTRUMENT.