Charles Flaum

US Patent:

6600315, Jul 29, 2003

Filed:

Dec 14, 2000

Appl. No.:

09/681061

Inventors:

Nicholas J. Heaton - Houston TX
Charles Flaum - Ridgefield CT
Chanh Cao Minh - Katy TX

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

C01V 300

US Classification:

324303

Abstract:

A method that is usable with an NMR measurement apparatus includes averaging first spin echo trains acquired from different regions of a sample to form a second spin echo train. The first spin echo trains are used to produce a first estimate of a property of the sample, and the first estimate has a first resolution and a first accuracy. The second spin echo train is used to produce a second estimate of the property, and the second estimate has a second resolution that is lower than the first resolution and a second accuracy that is higher than the first accuracy. The first and second estimates are combined to produce a third estimate of the property. The third estimate has a third resolution near the first resolution of the first estimate and a third accuracy near the second accuracy of the second estimate.

US Patent:

7642507, Jan 5, 2010

Filed:

Feb 15, 2006

Appl. No.:

11/307632

Inventors:

Richard J. Radtke - Pearland TX, US
Michael Evans - Missouri City TX, US
Charles Flaum - Ridgefield CT, US

Assignee:

Schlumberger Technology Corporation - Sugar Land TX

International Classification:

G01V 5/12

US Classification:

250256, 2502693, 250265, 250261

Abstract:

A tool for formation logging includes a support configured for movement in a borehole; a source mounted on the support, the source configured to emit neutrons and gamma rays; and at least one sensor mounted on the support and spaced apart from the source, wherein the at least one sensor is configured to detect at least one selected from the group consisting of gamma rays and neutrons. A method for formation logging in accordance with one embodiment of the invention includes emitting neutrons and gamma rays into a formation, using a source on a logging tool disposed in a borehole penetrating the formation; and detecting gamma-ray signals and neutron signals scattered by the formation, using at least one detector on the logging tool.

US Patent:

6232778, May 15, 2001

Filed:

Jun 11, 1998

Appl. No.:

9/096320

Inventors:

Peter Speier - Stafford TX
Steven F. Crary - Sugar Land TX
Robert L. Kleinberg - Ridgefield CT
Charles Flaum - Ridgefield CT

Assignee:

Schlumberger Technology Corporation

International Classification:

G01V 300

US Classification:

324303

Abstract:

The present invention provides methods for determining the bound fluid volume (BFV) of a formation utilizing nuclear magnetic resonance (NMR) techniques in which less than full polarization occurs and in which less than a complete NMR distribution is acquired. The effect of the polarizing static magnetic field is shortened in time by applying a shortened wait time between NMR measurements so that only the bound fluid of the formation is polarized. The shortened wait time is effectuated by early application of the oscillating magnetic field to the formation which, in conjunction with a limited number of refocusing pulses, induces signals in the formation that are measured by the NMR tool. The peak amplitude of these signals corresponds to the BFV. The present invention provides information so that a partial polarization calculation curve in T. sub.

US Patent:

49090755, Mar 20, 1990

Filed:

Sep 7, 1989

Appl. No.:

7/405396

Inventors:

Charles Flaum - Houston TX
James E. Galford - Sugarland TX
Steven W. Duckett - Los Altos Hills CA

Assignee:

Schlumberger Technology Corporation - Houston TX

International Classification:

E21B 4700

US Classification:

73152

Abstract:

A method for determining a characteristic of a subsurface geological formation enhances the vertical resolution of dual-detector measurements by utilizing a continuous calibration factor which is obtained from an environmentally compensated characteristic derived from at least two resolution-matched sensor signals, and from a resolution-matched sensor signal from the near-detector of the tool. This method also can enhance the statistical precision of the characteristic without degrading the vertical resolution.

US Patent:

47947926, Jan 3, 1989

Filed:

Mar 3, 1988

Appl. No.:

7/164367

Inventors:

Charles Flaum - Houston TX
James E. Galford - Sugarland TX
Steven W. Ducket - Palo Alto CA

Assignee:

Schlumberger Technology Corporation - Houston TX

International Classification:

E21B 4900

US Classification:

73152

Abstract:

A method for determining a characteristic of a subsurface geological formation enhances the vertical resolution of dual-detector measurements by utilizing a continuous calibration factor which is obtained from an environmentally compensated characteristic derived from at least two resolution-matched sensor signals, and from a resolution-matched sensor signal from the near-detector of the tool.

US Patent:

47867965, Nov 22, 1988

Filed:

Oct 3, 1986

Appl. No.:

6/915439

Inventors:

Charles Flaum - Houston TX
James E. Galford - Sugarland TX
Steven V. Ducket - Palo Alto CA

Assignee:

Schlumberger Technology Corporation - Houston TX

International Classification:

G01V 508

US Classification:

250266

Abstract:

A method for determining a characteristic of a subsurface geological formation enhances the vertical resolution of dual-detector measurements by utilizing a continuous calibration factor which is obtained from an environmentally compensated characteristic derived from at least two resolution-matched sensor signals, and from a resolution-matched sensor signal from the near-detector of the tool.

US Patent:

48166740, Mar 28, 1989

Filed:

Jun 29, 1987

Appl. No.:

7/067898

Inventors:

Darwin V. Ellis - Ridgefield CT
Charles Flaum - Houston TX
Hubert D. Scott - Katy TX

Assignee:

Schlumberger Technology Corporation - New York NY

International Classification:

G01V 510

US Classification:

250266

Abstract:

A method for determining the porosity of a subsurface geological formation traversed by a borehole is provided. The method generally comprises obtaining a means which relates ranges of apparent formation porosity (. phi. sub. a) as determined by a neutron-neutron log, formation fluid salinities, formation total capture cross sections (. SIGMA. ), formation matrix and fluid constituents, and true formation porosity (. phi. sub. T) according to a predetermined equation. The predetermined equation relates the apparent porosity to a function of a modified migration length which is obtained in a semi-empirical manner (i. e. physics modifed by data). The modified migration length includes a slowing down length and a diffusion length, but causes at least the diffusion length to be a function of the slowing down length. The means which relates the apparent porosity to salinity,. SIGMA. , matrix and fluid constituents, and. phi. sub.

US Patent:

61474894, Nov 14, 2000

Filed:

Jun 12, 1997

Appl. No.:

8/873981

Inventors:

Robert Freedman - Houston TX
Christopher Morriss - The Woodlands TX
Austin Boyd - Halifax, CA
Charles Flaum - Ridgefield CT

Assignee:

Schlumberger Technology Corporation - Houston TX

International Classification:

G01V 300

US Classification:

324303

Abstract:

A method and apparatus for determining gas corrected porosity using nuclear magnetic resonance (NMR) and density measurements is disclosed. The total porosity (TCMR) or an earth formation is determined using an NMR tool. A log output is generated that indicates the density of the formation. The density porosity of the formation is determined from the log output. The difference between the TCMR-density porosity log accurately indicates the presence of gas. A gas corrected porosity,. phi. , and gas saturation, S. sub. g, are determined based upon the density porosity and TCMR.