Edward A Nichols

US Patent:

6393363, May 21, 2002

Filed:

Dec 15, 2000

Appl. No.:

09/719788

Inventors:

Michael Wilt - Walnut Creek CA
Edward Nichols - Berkeley CA

Assignee:

Schlumberger Technology Corporation - Houston TX

International Classification:

G06F 1900

US Classification:

702 6, 324323

Abstract:

Provided are a method, a computer program product and a system, to measure characteristics of a geologic formation, such as hydrocarbon reservoirs, that employs modeling data to remove unwanted information from a signal carrying information concerning the geologic formation. This allows obtaining accurate information concerning the resistivity of geologic formations in which a borehole has been formed and encased with a conductive liner, such as a steel casing. Specifically, it was recognized that a magnetic field produced within a borehole that has been cased is substantially similar to magnetic field produced from a borehole that was not cased, i. e. , the spatial distribution and orientation to the two aforementioned magnetic fields are the same, differing only by a constant related to the casing attenuation factor. The magnetic field outside of the cased borehole is reduced in amplitude by an attenuation factor associated with the liner. Thus, the magnetic field produced at a point outside of the liner is a function of the product of term for the attenuation factor of the liner, k and a term for the response of the geologic formation, Æ.

US Patent:

6534986, Mar 18, 2003

Filed:

Apr 18, 2001

Appl. No.:

09/837104

Inventors:

Edward Nichols - Berkeley CA

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

G01V 300

US Classification:

324339, 324346, 16625016, 3408548

Abstract:

Systems and methods for determining characteristics of geologic formations between conductively lined wellbores. At least one transmitter is axially disposed at a selected depth in a first wellbore and is attached to an external surface of a conductive liner. At least one receiver is axially disposed at a selected depth in a second wellbore and is attached to an external surface of a conductive liner. Both the transmitter and the receiver are attached to a surface control station. The transmitter generates a first magnetic field, and a formation magnetic field induced by the first magnetic field is detected by the receiver. The detected formation magnetic field is used to determine characteristics of the geologic formations.

US Patent:

6597178, Jul 22, 2003

Filed:

Oct 18, 2002

Appl. No.:

10/065454

Inventors:

Edward Nichols - Berkeley CA
Ugo Conti - El Cerrito CA
Dzevat Omeragic - Sugar Land TX

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

G01V 310

US Classification:

324339, 324346, 702 11

Abstract:

A magnetic receiver with a magnetically permeable core is positioned inside a wellbore casing and operated in a feedback mode to reduce attenuation of a measurable magnetic field. The receiver employs a feedback device to reduce mutual coupling between the core and the casing, which reduces the otherwise normal attenuation of em signals inside the casing. The feedback device may be provided in the form of an extra or feedback winding that effectively cancels the inducing field inside the core and reduces the attenuation otherwise caused by the core-casing interaction. Alternatively, the magnetic receiver may employ, as the feedback device, a current feedback amplifier circuit to cancel the inducing field inside the core. Specifically, the circuit is operated to produce a secondary magnetic field that essentially cancels the inducing field inside the core.

US Patent:

6842006, Jan 11, 2005

Filed:

Jun 27, 2002

Appl. No.:

10/185105

Inventors:

Ugo Conti - El Cerrito CA, US
Edward Nichols - Berkeley CA, US

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

G01V 315
G01V 308

US Classification:

324350, 324348, 324365

Abstract:

A sea-floor electromagnetic measurement device for obtaining underwater measurements of earth formations including a central structure and arms attached to the central structure so that they can pivot relative to the central structure. An electrode is attached to the end of each of the arms or to the central structure, and/or magnetometers are attached to the arms. A method for undertaking sea-floor electromagnetic measurements of earth formations including measuring electric fields at a selected distance from a central structure of an electromagnetic measurement system. Magnetic fields are then measured at the same location.

US Patent:

7023213, Apr 4, 2006

Filed:

Dec 10, 2002

Appl. No.:

10/315795

Inventors:

Edward Nichols - Berkeley CA, US

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

G01V 3/00

US Classification:

324348

Abstract:

A subsurface imaging cable includes a plurality of sensor modules, wherein the plurality of the sensor modules are flexible and each of the plurality of the sensor modules is spaced apart on the subsurface imaging cable at a selected distance; and a flexible medium connecting the plurality of the sensor modules, wherein the subsurface imaging cable is flexible and adapted to be wound on a reel. A method for subsurface images includes acquiring direct-current measurements at a plurality of sites in a survey area; acquiring a first set of electric and magnetic measurements from natural electromagnetic fields at the plurality of sites; acquiring a second set of electric and magnetic measurements using controlled electric and magnetic sources at the plurality of sites; and determining a subsurface conductivity distribution from the direct-current measurements and the first set and the second set of electric and magnetic measurements.

US Patent:

7295013, Nov 13, 2007

Filed:

Apr 11, 2005

Appl. No.:

10/907657

Inventors:

Ugo Conti - El Cerrito CA, US
Edward Nichols - Berkeley CA, US

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

G01V 3/08
G01V 3/00

US Classification:

324350, 324348, 324365

Abstract:

A marine measurement system is disclosed for obtaining measurements in an underwater operating environment. The system includes a base structure having a top surface, a bottom surface, and cavities provided therebetween. The cavities are also open to the top surface. The measurement system further includes measurement equipment (e. g. , electronic equipment and/or instrumentation), which are retained in the cavities. A diaphragm membrane is applied adjacent the top surface and seals the cavities. The diaphragm member is positioned in pressure communication with the operating environment. Furthermore, the cavities are defined by the membrane and the base structure and filled with a pressure compensating fluid that is in pressure communication with the operating environment through the diaphragm membrane.

US Patent:

7565244, Jul 21, 2009

Filed:

Jun 27, 2007

Appl. No.:

11/768975

Inventors:

David Alumbaugh - Berkeley CA, US
Ping Zhang - Albany CA, US
Edward Nichols - Berkeley CA, US
Frank Morrison - Berkeley CA, US
Aria Abubakar - North Reading MA, US
Tarek Habashy - Burlington MA, US

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

G01V 1/40

US Classification:

702 6, 702 7, 702 11, 324323, 324334, 324339, 367 29, 367 49

Abstract:

Characterizing a reservoir with electromagnetic imaging surveys includes normalizing measured voltage data by transmitter moment, sorting the normalized voltage data into common receiver profiles, densely resampling transmitter locations using common positions for the receiver profiles, coarsely resampling the data at discreet transmitter locations, defining a starting model for inversion, weighting the data by a factor, converting the normalized voltage data to ratios, calculating a conductivity image using a ratio inversion method, and verifying that an inversion has converged and the image is geologically reasonable. The image can then be displayed. The invention can be used for cross-well, surface-to-borehole, and borehole-to-surface measurements by which the effects of steel casing are reduced.

US Patent:

7633296, Dec 15, 2009

Filed:

Mar 30, 2007

Appl. No.:

11/694179

Inventors:

Kambiz Safinya - Garches, FR
Edward Nichols - Berkeley CA, US
Kamal Babour - Bures sur Yvette, FR
Philip Heelan - County Clare, IE
Christian Besson - Le Pecq, FR

Assignee:

WesternGeco L.L.C. - Houston TX

International Classification:

G01V 3/00

US Classification:

324347, 324365

Abstract:

A receiver for electromagnetic measurements includes a polyhedron structure having m faces, where m≧4 and m≠6: n electrodes each disposed on one face of the polyhedron structure, wherein 3≦n≦m; and at least one circuitry connected to the n electrodes for signal measurement. A method for electromagnetic measurements includes obtaining a plurality of electric current measurements using a plurality of electrodes each disposed on a surface of a polyhedron receiver, wherein the plurality of electric current measurements comprise at least three different measurements; and determining electric field components in a three dimensional space from the plurality of electric current measurements by using a number of matrices that correlate orientations of surfaces of the polyhedron receiver to a coordinate system in the three dimensional space.