Schlumberger Technology Corporation

Services Petroliers Schlumberger

Schlumberger Holdings Limited

Prad Research and Development Limited

William B Vandermeer

Andrei Davydychev

Bulent Finci

John F Hunka

Scott S Chesser

Richard Dan Ward

Thomas D Barber

Jingjing (Karen) Sun

Yi-Qiao Song

Dean M Homan

Edward Harrigan

Anthony Louis Collins

Srinand Sreedharan Karuppoor

Andrew John Carnegie

Mark A Fredette

Henry N Bachman

Yves Barriol

William D Flanagan

Tim Hopper

Jingjing Karen Sun

Denis Lebreton

Andrei I Davydychev

Andrew J Carnegie

Subsurface formation evaluation comprising, for example, sealing a portion of a wall of a wellbore penetrating the formation, forming a hole through the sealed portion of the wellbore wall, injecting an injection fluid into the formation through the hole, and determining a saturation of the injection fluid in the formation by measuring a property of the formation proximate the hole while maintaining the sealed portion of the wellbore wall.

Formation evaluation instrument and method

An electromagnetic logging tool is disclosed that includes a support; and at least one four-coil array disposed on the support, wherein the at least one four-coil array comprises: a transmitter, a bucking coil, a receiver, and a trim coil. A method for balancing an induction array is disclosed that includes applying an alternating current to a transmitter of the induction array that comprises the transmitter, a bucking coil and a receiver; measuring a mutual coupling between the transmitter and the receiver; and adding an extra bucking coil, if the mutual coupling exceeds a selected criterion.

Extra bucking coils to balance induction arrays

An electromagnetic logging tool includes a support configured for disposal in a well; at least one antenna mounted on the support; and a plurality of coils mounted on the support proximate the at least one antenna, wherein the plurality of the coils are configured for selective connection with the at least one antenna. A methods for balancing an induction array on an electromagnetic logging tool includes measuring a mutual coupling between a transmitter and a receiver on the electromagnetic logging tool; and selectively connecting a subset of a plurality of coils on the electromagnetic logging tool to the transmitter or the receiver based on the measured mutual coupling.

Selectable tap induction coil

A composite encased tool for making subsurface measurements in a borehole traversing a subsurface formation includes a conductive mandrel, a first composite layer wrapped around the conductive mandrel, the first composite layer having one or more slots, a source or sensor disposed in each of the one or more slots, and a second composite layer wrapped around the first composite layer with the source or sensor in the one or more slots.

Composite encased tool for subsurface measurements

An electromagnetic logging that includes a support; and at least one four-coil array disposed on the support, wherein the at least one four-coil array comprises: a transmitter, a bucking coil, a receiver, and a trim coil. A method for balancing an induction array includes applying an alternating current to a transmitter of the induction array that comprises the transmitter, a bucking coil and a receiver; measuring a mutual coupling between the transmitter and the receiver; and adding an extra bucking coil, if the mutual coupling exceeds a selected criterion.

Extra bucking coils as an alternative way to balance induction arrays

An electromagnetic logging tool includes a support configured for disposal in a well; at least one antenna mounted on the support; and a plurality of coils mounted on the support proximate the at least one antenna, wherein the plurality of the coils are configured for selective connection with the at least one antenna. A method for balancing an induction array on an electromagnetic logging tool includes measuring a mutual coupling between a transmitter and a receiver on the electromagnetic logging tool; and selectively connecting a subset of a plurality of coils on the electromagnetic logging tool to the transmitter or the receiver based on the measured mutual coupling.

A method for determining a sonde error characteristic of an induction tool is disclosed. The method includes the step of measuring an electrical characteristic which may be the real or quadrature component of conductivity, at two or more different heights above the earth. The sonde error characteristic is determined as a function of a predetermined relationship between the desired sonde error characteristic and the measurements of that characteristic at two or more different heights above the earth. The method may be performed with the tool disposed substantially parallel to the earth. Alternatively, the tool may be disposed substantially perpendicularly to the earth.

Method for determining induction sonde error

Growing community of inventors

Houston, TX, United States of America

William B Vandermeer