Gregory Boris Itskovich

US Patent:

6353322, Mar 5, 2002

Filed:

Jun 9, 1998

Appl. No.:

09/094220

Inventors:

Leonty Abraham Tabarovsky - Houston TX
Gregory Boris Itskovich - Houston TX

Assignee:

Baker Hughes Incorporated - Houston TX

International Classification:

G01V 320

US Classification:

324366, 324358, 324371

Abstract:

A method for determining the resistivity of earth formations penetrated by a wellbore. Electrical current is imparted to the wellbore and the earth formations from a first electrode located on a mandrel disposed in the wellbore. The electrical current is returned at a second electrode on the mandrel at a spaced apart location from the first electrode. Voltage differences are measured between a first pair and a second pair of electrodes located on the mandrel between the first and the second electrodes. Circuits used to measure the voltage differences are adjusted until the measured voltage difference between the second pair is substantially the same as the measured voltage difference between the first pair. Then the electrical current is returned to an electrode at the earths surface or other location distal from the first electrode, and measuring the voltage differences is repeated. A difference of the voltage differences is then calculated.

US Patent:

6429654, Aug 6, 2002

Filed:

Sep 28, 2000

Appl. No.:

09/672413

Inventors:

Gregory Itskovich - Houston TX
Arcady Reiderman - Houston TX

Assignee:

Baker Hughes Incorporated - Houston TX

International Classification:

G01V 300

US Classification:

324314, 324303

Abstract:

A method for acquiring nuclear magnetic resonance measurements of a material uses a gradient tool. A modified CPMG sequence is used wherein the duration of the refocusing pulse is selected to maximize the SNR of the pulse echoes relative to a standard CPMG sequence in which the refocusing pulse has twice the duration of the tipping pulse.

US Patent:

6437564, Aug 20, 2002

Filed:

May 1, 2001

Appl. No.:

09/846971

Inventors:

Gregory Boris Itskovich - Houston TX
David Beard - Houston TX
Arcady Reiderman - Houston TX

Assignee:

Baker Hughes Incorporated - Houston TX

International Classification:

G01V 300

US Classification:

324303, 324300

Abstract:

The static magnetic field of a permanent magnet used in an NMR tool moves with the tool. NMR measurements made with a moving tool are affected by incomplete polarization of the nuclear spins in the region where the Larmor frequency of static field matches the RF signal frequency. Simulation results show that the in-phase and quadrature components of spin echo signals are affected by the velocity of lateral motion of a logging tool in a borehole. A phase drift indicator is obtained by summing the quadrature and in-phase components over a window and taking the ratio of the windowed sums. The phase drift indicator shows an increase with time. In a tool with a gradient magnetic field, the phase drift indicator increases with time even for no tool motion. The reduction in magnitude of spin echo data due to tool motion alone may be obtained by comparing the magnitude of simulated echoes with and without tool motion.

US Patent:

6597170, Jul 22, 2003

Filed:

Jun 29, 2000

Appl. No.:

09/606998

Inventors:

David Beard - Houston TX
Gregory Itskovich - Houston TX
Arcady Reiderman - Houston TX
Songhua Chen - Katy TX

Assignee:

Baker Hughes Incorporated - Houston TX

International Classification:

G01V 300

US Classification:

324303

Abstract:

Pulse shaping is used for reducing the interference between echo trains of multiple frequency NMR logging applications in a gradient logging tool. The major contribution to the interference between different logging sequences comes from the sidelobes in the spectra of the excitation signal caused by modulating the RF signal with a square pulse. By shaping the tipping pulse in a CPMG pulse sequence, the interference between logging sequences at proximate frequencies is reduced. The shaped pulse may be a smooth function such as the Chebyshev function or it may be a composite of two rectangular pulses. In an alternate embodiment of the invention, the refocusing pulses are also shaped.

US Patent:

6903553, Jun 7, 2005

Filed:

Mar 14, 2003

Appl. No.:

10/388871

Inventors:

Gregory Itskovich - Houston TX, US
Alexander Bespalov - Spring TX, US
Borislav J. Tchakarov - Houston TX, US

Assignee:

Baker Hughes Incorporated - Houston TX

International Classification:

G01V003/10

US Classification:

324339, 324338

Abstract:

The present invention provides a method and apparatus for performing resistivity measurements for the purpose of geo-steering with 180-degree azimuth resolution. All the measurements represent a complementary set of data acquired in two operational modes. The directional mode providing sensitivity of the received signals to the azimuth characteristics of the formation. The deep mode provides a large depth of investigation for resistivity determination and bed boundary detection. The directional mode can be implemented using one receiving coil placed in between quadruple type transmitter. The deep mode represents either array induction measurements or multiple propagation resisitivity (MPR) measurements that provide high depth of investigation for resistivity determination and bed boundary detection.

US Patent:

6937022, Aug 30, 2005

Filed:

Jul 1, 2003

Appl. No.:

10/610943

Inventors:

Gregory Itskovich - Houston TX, US
Alexander Bespalov - Spring TX, US
Borislav J. Tchakarov - Houston TX, US

Assignee:

Baker Hughes Incorporated - Houston TX

International Classification:

G01V003/08

US Classification:

324339, 324346

Abstract:

The present invention provides a method and apparatus for performing resistivity measurements for the purpose of geo-steering with 180-degree azimuth resolution. All the measurements represent a complementary set of data acquired in two operational modes. The directional mode providing sensitivity of the received signals to the azimuth characteristics of the formation. The deep mode provides a large depth of investigation for resistivity determination and bed boundary detection. The directional mode can be implemented using one receiving coil placed in between quadruple type transmitter. The deep mode represents either array induction measurements or multiple propagation resisitivity (MPR) measurements that provide high depth of investigation for resistivity determination and bed boundary detection.

US Patent:

7046009, May 16, 2006

Filed:

Dec 24, 2003

Appl. No.:

10/746071

Inventors:

Gregory Itskovich - Houston TX, US

Assignee:

Baker Hughes Incorporated - Houston TX

International Classification:

G01V 3/08
G01V 3/10

US Classification:

324338, 324339

Abstract:

A transverse induction transmitter on an instrument induces currents in an earth formation when it is pulsed. Transient measurements made at transverse and axial receivers are used for determination of a distance to a bed boundary. This may be used to control the drilling direction. Alternatively, a transmitter on an instrument having a conductive body induces currents in the earth formation. Transient signals are measured and the effect of the conductive body is removed by using a reference signal measured in a homogenous space.

US Patent:

7049815, May 23, 2006

Filed:

Jan 27, 2004

Appl. No.:

10/765612

Inventors:

Gregory Itskovich - Houston TX, US
Arcady Reiderman - Houston TX, US

Assignee:

Baker Hughes Incorporated - Houston TX

International Classification:

G01V 3/00

US Classification:

324303, 324306

Abstract:

Pulse sequences are applied to a fluid in an earth formation in a static magnetic field having internal gradients. From the received signals, relaxation and diffusion characteristics of the fluid are determined. The determination takes into account the internal field gradients.