Li Gao

US Patent:

6393364, May 21, 2002

Filed:

May 30, 2000

Appl. No.:

09/583184

Inventors:

Li Gao - Missouri City TX
Stanley C. Gianzero - Austin TX

Assignee:

Halliburton Energy Services, Inc. - Houston TX

International Classification:

G01V 140

US Classification:

702 7, 702 10, 324339

Abstract:

A method is disclosed for the determination of horizontal resistivity, vertical resistivity, dip and strike angles of anisotropic earth formations surrounding a wellbore. Electromagnetic couplings among a plural of triad transmitters and triad receivers are measured. Each triad transmitter/receiver consists of coil windings in three mutually orthogonal axes. These measured signals are used to generate initial estimates of the dip angle and strike angle of the formation as well as the anisotropy coefficient and the horizontal resistivity of the formation. An iterative algorithm is then applied using these quantities to finally arrive at more accurate estimates that approach the true values in the formation.

US Patent:

6556016, Apr 29, 2003

Filed:

Aug 10, 2001

Appl. No.:

09/927818

Inventors:

Li Gao - Missouri City TX
Luis SanMartin - Houston TX
Stanley C. Gianzero - Austin TX

Assignee:

Halliburton Energy Services, Inc. - Houston TX

International Classification:

G01V 328

US Classification:

324343, 702 7

Abstract:

A method is disclosed for the determination of the dip angle of anisotropic earth formations surrounding a wellbore. Electromagnetic couplings among a plural of triad transmitters and triad receivers are measured. Each triad transmitter/receiver consists of coil windings in three mutually orthogonal axes. The transmitter coils and receiver coils are oriented such that mutually symmetrical transmitter pairs or mutually symmetrical receiver pairs are equidistant from a centrally located receiver or transmitter, respectively. The measured signals from the created couplings are used to generate initial separate estimates of the dip angle of the formation. The two discrete determination is of dip angle are then averaged to arrive at a more accurate estimate that approaches the true dip angle in the formation.

US Patent:

6611762, Aug 26, 2003

Filed:

Apr 4, 2002

Appl. No.:

10/116472

Inventors:

Li Gao - Missouri City TX

Assignee:

Halliburton Energy Services, Inc. - Dallas TX

International Classification:

G06F 1900

US Classification:

702 7, 324339

Abstract:

A method for determining a formation profile surrounding a well bore includes receiving field log data for the formation and generating a Jacobian matrix responsive to the provided field log data. A quasi-Newton update is used to update the Jacobian matrix for each necessary iteration until a generated formation profile converges with the received field log data.

US Patent:

6727706, Apr 27, 2004

Filed:

Aug 9, 2001

Appl. No.:

09/925997

Inventors:

Li Gao - Missouri City TX
Stanley C. Gianzero - Austin TX

Assignee:

Halliburton Energy Services, Inc. - Houston TX

International Classification:

G01V 318

US Classification:

324339, 702 7

Abstract:

A method is disclosed for using a triad induction tool to identify the formation strike and dip angles. The method can be performed in real time. In one embodiment, the method includes: (1) measuring a magnetic coupling between transmitter coils and receiver coils of a tool in the borehole; (2) obtaining from the measured coupling a strike angle between the tool and the formation; (3) applying a rotational transformation to the coupling measurements to correct for the strike angle; and (4) applying a predetermined set of rotational transformations to the coupling to determine coupling term values as a function of rotation angle. A least-squares curve fit or a Hough transform of the derivative of the coupling term values with respect to position may be used to identify the dip angle.

US Patent:

6765386, Jul 20, 2004

Filed:

Apr 10, 2002

Appl. No.:

10/119891

Inventors:

Stanley C. Gianzero - Austin TX
Li Gao - Missouri City TX

Assignee:

Halliburton Energy Services, Inc. - Houston TX

International Classification:

G01V 320

US Classification:

324367, 324371

Abstract:

A logging tool is disclosed for measuring the resistive anisotropy of formations around a borehole. The logging tool includes a set of electrodes that contact a wall of the borehole. The set of electrodes includes a first pair of current electrodes spaced apart vertically, and a second pair of current electrodes spaced apart horizontally. Between the first and second pair of current electrodes are two or more measurement electrodes that measure a vertical axis voltage difference and a horizontal axis voltage difference caused by currents flowing between the pairs of current electrodes. A resistive anisotropy can be calculated from the measured voltage differences. A third pair of current electrodes oriented perpendicularly with respect to the first and second pair of current electrodes may be provided with corresponding measurement electrodes if it is desired to measure the biaxial resistive anisotropy of the formation.

US Patent:

6819112, Nov 16, 2004

Filed:

Feb 5, 2002

Appl. No.:

10/068346

Inventors:

Stanley C. Gianzero - Austin TX
Li Gao - Missouri City TX

Assignee:

Halliburton Energy Services, Inc. - Houston TX

International Classification:

G01V 328

US Classification:

324343, 702 7

Abstract:

There is disclosed herein a method of enhancing the vertical resolution of an induction tool, in a manner that may advantageously also reduce undesirable borehole and ânegative resistivityâ effects. In one embodiment, the method comprises: a) obtaining a vertical magnetic dipole (VMD) response signal from a transmitter-receiver array of antenna elements having magnetic dipoles oriented parallel to a tool axis; b) obtaining a horizontal magnetic dipole (HMD) response signal from a transmitter-receiver array of elements having magnetic dipoles oriented perpendicular to the tool axis; and c) combining the VMD and HMD response signals to obtain a combination response signal. When the relative weights of the VMD and HMD response signals are set as described herein, the combination response signal (and any log calculated therefrom) has a narrow, substantially rectilinear, vertical measurement profile. Further, the combination response signal is relatively insensitive to borehole effects.

US Patent:

6859733, Feb 22, 2005

Filed:

Aug 20, 2003

Appl. No.:

10/644327

Inventors:

Li Gao - Missouri City TX, US

Assignee:

Halliburton Energy Services, Inc. - Houston TX

International Classification:

G01V003/18

US Classification:

702 7, 324339

Abstract:

A method for determining a formation profile surrounding a well bore includes receiving field log data for the formation and generating a Jacobian matrix responsive to the provided field log data. A quasi-Newton update is used to update the Jacobian matrix for each necessary iteration until a generated formation profile converges with the received field log data.

US Patent:

6898529, May 24, 2005

Filed:

Sep 5, 2003

Appl. No.:

10/657018

Inventors:

Li Gao - Missouri City TX, US
Lewis Norman - Duncan OK, US

Assignee:

Halliburton Energy Services, Inc. - Duncan OK

International Classification:

G06F019/00

US Classification:

702 11, 702 13

Abstract:

The present invention is directed to a method and system for determining parameters inside a subterranean formation. In accordance with the present invention, a plurality of wireless data sensors are injected into the pores or fractures of a subterranean formation. The data sensors includes sensors that record parameters such as temperature, pressure and certain time stamps. Either autonoumously or upon command from a data interrogator tool located down hole, the plurality of data sensors form a wireless ad hoc network and telemeter the recorded data back to the data interrogator tool, which in turn communicates the data to a microprocessor located at the surface. Based on these data, the spatial distribution of the sensors and formation parameters such as temperature and pressure at each data sensor inside the subterranean formation can be obtained.