Well operation depth control method

Claim 1

A METHOD FOR PERFORATING IN A WELL PENETRATING AT LEAST TWO VERTICALLY SPACED, UPPER AND LOWER PRODUCTIVE FORMATIONS AND CONTAINING AT LEAST TWO JUXTAPOSED PIPE STRINGS, ONE OF WHICH CONTAINS AT LEAST ONE RADIOACTIVITY MARKER POSITIONED ALONG THE LENGTH THEREOF COMPRISING RUNNING IN SAID ON PIPE STRING A RADIOACTIVITY SURVEY TOOL TOGETHER WITH A COLLAR LOCATOR TOOL, AND PREPARING THEREFROM A CORRELATION LOG SHOWING THE LOCATIONS OF SAID PRODUCTIVE FORMATIONS, THE LOCATIONS OF THE PIPE COLLARS OF SAID ONE PIPE STRING, AND THE POSITION OF SAID RADIOACTIVITY MARKER RELATIVE TO EACH OTHER; LOWERING IN SAID OTHER PIPE STRING A DEVICE PROVIDED WITH A PERFORATOR HAVING A SELECTED DIRECTION OF PERFORATION, AND WITH RADIATION MEANS HAVING A SELECTED DIRECTION OF PIPE DETECTION INCLUDING A SOURCE OF RADIATION AND A DETECTOR OF BOTH RADIATION RESULTING FROM INTERACTIONS OF SAID SOURCE RADIATION AND DIRECT RADIATION EMANATING FROM SAID MARKER, AND WITH MEANS FOR CAUSING ROTATION OF SAID DEVICE, TO THE DEPTH OF SAID RADIOACTIVITY MARKER BY DETECTION OF SAID RADIOACTIVITY MARKER BY SAID DETECTOR; MOVING SAID DEVICE THE DISTANCE BETWEEN SAID RADIOACTIVITY MARKER AND SAID UPPER FORMATION AS SHOWN ON SAID CORRELATION LOG TO POSITION SAID DEVICE ADJACENT SAID UPPER FORMATION; ROTATING SAID DEVICE, TO LOCATE THE POSITION OF SAID ONE PIPE STRING RELATIVE TO A REFERENCE POSITION OF SAID DEVICE, AND ACCORDINGLY, TO SAID DIRECTION OF PIPE DETECTION AND SAID DIRECTION OF PERFORATION, WITH SAID RADIATION MEANS; FURTHER ROTATING SAID DEVICE TO DIRECT THE DIRECTION OF PERFORATION AWAY FROM SAID ONE PIPE STRING; AND THEN ACTUATING SAID PERFORATOR TO PERFORATE SAID UPPER FORMATION.

Claim 2

A METHOD FOR PERFORATING IN A WELL PENETRATING AT LEAST TWO VERTICALLY SPACED, UPPER AND LOWER PRODUCTIVE FORMATIONS AND CONTAINING AT LEAST TWO JUXTAPOSED PIPE STRINGS, ONE OF WHICH CONTAINS AT LEAST ONE RADIOACTIVITY MARKER POSITIONED ALONG THE LENGTH THEREOF COMPRISING RUNNING IN SAID ON PIPE STRING A RADIOACTIVITY SURVEY TOOL TOGETHER WITH A COLLAR LOCATOR TOOL, AND PREPARING THEREFROM A CORRELATION LOG SHOWING THE LOCATIONS OF SAID PRODUCTIVE FORMATIONS, THE LOCATIONS OF THE PIPE COLLARS OF SAID ONE PIPE STRING, AND THE POSITION OF SAID RADIOACTIVITY MARKER RELATIVE TO EACH OTHER; LOWERING IN SAID OTHER PIPE STRING A DEVICE PROVIDED WITH A PERFORATOR HAVING A SELECTED DIRECTION OF PERFORATION, AND WITH RADIATION MEANS HAVING A SELECTED DIRECTION OF PIPE DETECTION INCLUDING A SOURCE OF RADIATION AND A DETECTOR OF BOTH RADIATION RESULTING FROM INTERACTIONS OF SAID SOURCE RADIATION AND DIRECT RADIATION EMANATING FROM SAID MARKER, AND WITH MEANS FOR CAUSING ROTATION OF SAID DEVICE, TO THE DEPTH OF SAID RADIOACTIVITY MARKER BY DETECTION OF SAID RADIOACTIVITY MARKER BY SAID DETECTOR; MOVING SAID DEVICE THE DISTANCE BETWEEN SAID RADIOACTIVITY MARKER AND SAID UPPER FORMATION AS SHOWN ON SAID CORRELATION LOG TO POSITION SAID DEVICE ADJACENT SAID UPPER FORMATION; ROTATING SAID DEVICE, TO LOCATE THE POSITION OF SAID ONE PIPE STRING RELATIVE TO A REFERENCE POSITION OF SAID DEVICE, AND ACCORDINGLY, TO SAID DIRECTION OF PIPE DETECTION AND SAID DIRECTION OF PERFORATION, WITH SAID RADIATION MEANS; FURTHER ROTATING SAID DEVICE TO DIRECT THE DIRECTION OF PERFORATION AWAY FROM SAID ONE PIPE STRING; AND THEN ACTUATING SAID PERFORATOR TO PERFORATE SAID UPPER FORMATION.