Schlumberger Technology Corporation

Harold L Snyder

David R Hall

Paula Turner

Clint Cook

Katie George

Paula Tumer

A downhole induction resistivity assembly that comprises a downhole tool string component. The tool string component comprises an induction transmitter. The transmitter is adapted to induce an induction field in the surrounding formation. A first induction receiver is spaced apart from the transmitter and is adapted to measure the induction field. A magnetic field generating mechanism is disposed adjacent on either or both sides of the transmitter and adapted to guide the transmitter's signal into the formation. A second induction receiver is disposed in close proximity to the magnetic field generating mechanism and is adapted to measure the magnetic field generated by the mechanism.

Logging tool with independently energizable transmitters

Resistivity receiver spacing

In one aspect an induction resistivity tool incorporated into a downhole tool string comprises an outer wall of a downhole component comprising an outer diameter and at least one induction transmitter assembly disposed along the outer diameter. The at least one transmitter assembly comprises at least one induction transmitter coil wound about at least one core. The at least one transmitter coil is adapted to project an induction signal outward from the outer wall when the at least one transmitter coil is carrying an electrical current. The transmitter assembly is adapted to create electromagnetic fields that originate the induction signal from outside the outer wall and substantially prevent the signal from entering the outer wall.

Externally guided and directed field induction resistivity tool

Growing community of inventors

Rockwell, TX, United States of America

Harold L Snyder