Patents by Inventor Libai Xu
Libai Xu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Patent number: 10451766Abstract: Methods of elemental imaging of a formation include acquiring spectral gamma ray measurement, acquiring a total gamma ray image, deriving structure information of the formation from the total gamma ray image, and applying the structure information to the spectral gamma ray measurement to form an elemental image. In the present methods, the structure information of the formation is derived from comparing the total gamma ray logs for each azimuthal sector to a derived total gamma ray log. The derived total gamma ray log is acquired from the total gamma ray image by summing over all azimuth bins or the spectral gamma ray measurement by summing over all energy bins.Type: GrantFiled: December 17, 2015Date of Patent: October 22, 2019Assignee: SCHLUMBERGER TECHNOLOGY CORPORATIONInventors: Libai Xu, Wei Yang, Jiaxin Wang
-
Patent number: 10101493Abstract: A method for correcting natural gamma ray measurements includes processing an acquired gamma ray spectrum in combination with elemental standard spectra and at least one standard mud activation spectrum to compute corrected natural gamma ray measurements. The gamma ray spectrum is acquired using a logging string employing a neutron source and a natural gamma ray sensor.Type: GrantFiled: August 26, 2016Date of Patent: October 16, 2018Assignee: SCHLUMBERGER TECHNOLOGY CORPORATIONInventors: Libai Xu, Jiaxin Wang
-
Publication number: 20180267199Abstract: Methods of elemental imaging of a formation include acquiring spectral gamma ray measurement, acquiring a total gamma ray image, deriving structure information of the formation from the total gamma ray image, and applying the structure information to the spectral gamma ray measurement to form an elemental image. In the present methods, the structure information of the formation is derived from comparing the total gamma ray logs for each azimuthal sector to a derived total gamma ray log. The derived total gamma ray log is acquired from the total gamma ray image by summing over all azimuth bins or the spectral gamma ray measurement by summing over all energy bins.Type: ApplicationFiled: December 17, 2015Publication date: September 20, 2018Inventors: Libai Xu, Wei Yang, Jiaxin Wang
-
Publication number: 20180059283Abstract: A method for correcting natural gamma ray measurements includes processing an acquired gamma ray spectrum in combination with elemental standard spectra and at least one standard mud activation spectrum to compute corrected natural gamma ray measurements. The gamma ray spectrum is acquired using a logging string employing a neutron source and a natural gamma ray sensor.Type: ApplicationFiled: August 26, 2016Publication date: March 1, 2018Inventors: Libai Xu, Jiaxin Wang
-
Patent number: 9823384Abstract: A method for estimating a drilling fluid flow rate in a subterranean wellbore includes processing an acquired gamma ray spectrum in combination with standard elemental spectra and at least one standard oxygen activation spectrum to compute an oxygen activation yield. The oxygen activation yield is further processed to estimate a drilling fluid flow rate and or to infer a borehole diameter change or a lost circulation event. The gamma ray spectrum is acquired using a logging string employing a neutron source and a natural gamma ray sensor.Type: GrantFiled: August 26, 2016Date of Patent: November 21, 2017Assignee: SCHLUMBERGER TECHNOLOGY CORPORATIONInventors: Jiaxin Wang, Libai Xu, Christian Stoller
-
Patent number: 9360585Abstract: A method for estimating a borehole independent porosity of a subterranean formation includes processing a neutron logging data point, preferably including average near and far detector neutron count rates with suitable input data to obtain the porosity estimate. The borehole independent formation porosity may be obtained without any compensation and without any reliance on the measurement or estimation of sensor standoff and/or borehole caliper.Type: GrantFiled: May 23, 2011Date of Patent: June 7, 2016Assignee: SCHLUMBERGER TECHNOLOGY CORPORATIONInventors: Libai Xu, Cornelis Huiszoon
-
Patent number: 9057794Abstract: A method for determining a bulk formation density using a neutron generator includes detected secondary gamma rays and evaluating the detected gamma rays according to pre-determined selection criteria. Selected gamma rays are then used to compute the formation density. The selection criteria may include, for example, a time delay between the detection of a neutron and an associated particle and/or a direction of propagation of the neutron.Type: GrantFiled: August 10, 2011Date of Patent: June 16, 2015Assignee: Schlumberger Technology CorporationInventors: Libai Xu, Kevin S. McKinny, Cornelis Huiszoon
-
Patent number: 8975574Abstract: A well-logging tool may be positioned within a borehole of a subterranean formation. The well-logging tool may include a housing having an interior defining a dual-detector receiving chamber extending longitudinally, and having first and second portions, and a first azimuthal radiation detector carried by the first portion of the dual-detector receiving chamber. The first azimuthal radiation detector may include a first gamma-ray detector and a first photodetector associated with the first gamma-ray detector. The well-logging tool may include a second spectral radiation detector carried by the second portion of the dual-detector receiving chamber. The second spectral radiation detector may include a second gamma-ray detector and a second photodetector associated with the second gamma-ray detector.Type: GrantFiled: May 23, 2013Date of Patent: March 10, 2015Assignee: Schlumberger Technology CorporationInventors: Cornelis Huiszoon, Libai Xu, Christian Stoller, Robert Little, Peter Wraight
-
Publication number: 20140346337Abstract: A well-logging tool may be positioned within a borehole of a subterranean formation. The well-logging tool may include a housing having an interior defining a dual-detector receiving chamber extending longitudinally, and having first and second portions, and a first azimuthal radiation detector carried by the first portion of the dual-detector receiving chamber. The first azimuthal radiation detector may include a first gamma-ray detector and a first photodetector associated with the first gamma-ray detector. The well-logging tool may include a second azimuthal radiation detector carried by the second portion of the dual-detector receiving chamber. The second azimuthal radiation detector may include a second gamma-ray detector and a second photodetector associated with the second gamma-ray detector.Type: ApplicationFiled: May 23, 2013Publication date: November 27, 2014Applicant: Schlumberger Technology CorporationInventors: Cornelis Huiszoon, Libai Xu, Christian Stoller
-
Publication number: 20140346336Abstract: A well-logging tool may be positioned within a borehole of a subterranean formation. The well-logging tool may include a housing having an interior defining a dual-detector receiving chamber extending longitudinally, and having first and second portions, and a first azimuthal radiation detector carried by the first portion of the dual-detector receiving chamber. The first azimuthal radiation detector may include a first gamma-ray detector and a first photodetector associated with the first gamma-ray detector. The well-logging tool may include a second spectral radiation detector carried by the second portion of the dual-detector receiving chamber. The second spectral radiation detector may include a second gamma-ray detector and a second photodetector associated with the second gamma-ray detector.Type: ApplicationFiled: May 23, 2013Publication date: November 27, 2014Inventors: Cornelis Huiszoon, Libai Xu
-
Patent number: 8803078Abstract: A neutron logging tool includes a neutron source and at least one position sensitive thermal or epithermal neutron detector. The logging tool further includes an electronic controller configured to estimate the axial location of detected neutrons. Measurement of the axial neutron flux distribution enables other formation and borehole parameters such as formation porosity and sensor standoff to be computed. In logging while drilling embodiments, a borehole caliper may also be computed form the axial neutron flux distribution.Type: GrantFiled: May 4, 2011Date of Patent: August 12, 2014Assignee: Schlumberger Technology CorporationInventors: Libai Xu, Kevin S McKinny, Cornelis Huiszoon, Christian Stoller
-
Publication number: 20130327933Abstract: A method for determining a bulk formation density using a neutron generator includes detected secondary gamma rays and evaluating the detected gamma rays according to pre-determined selection criteria. Selected gamma rays are then used to compute the formation density. The selection criteria may include, for example, a time delay between the detection of a neutron and an associated particle and/or a direction of propagation of the neutron.Type: ApplicationFiled: August 10, 2011Publication date: December 12, 2013Applicant: SCHLUMBERGER TECHNOLOGY CORPORATIONInventors: Libai Xu, Kevin S. McKinny, Cornelis Huiszoon
-
Publication number: 20120303280Abstract: A method for estimating a borehole independent porosity of a subterranean formation includes processing a neutron logging data point, preferably including average near and far detector neutron count rates with suitable input data to obtain the porosity estimate. The borehole independent formation porosity may be obtained without any compensation and without any reliance on the measurement or estimation of sensor standoff and/or borehole caliper.Type: ApplicationFiled: May 23, 2011Publication date: November 29, 2012Applicant: SMITH INTERNATIONAL, INC.Inventors: Libai Xu, Cornelis Huiszoon
-
Publication number: 20110272570Abstract: A neutron logging tool includes a neutron source and at least one position sensitive thermal or epithermal neutron detector. The logging tool further includes an electronic controller configured to estimate the axial location of detected neutrons. Measurement of the axial neutron flux distribution enables other formation and borehole parameters such as formation porosity and sensor standoff to be computed. In logging while drilling embodiments, a borehole caliper may also be computed form the axial neutron flux distribution.Type: ApplicationFiled: May 4, 2011Publication date: November 10, 2011Applicant: SMITH INTERNATIONAL, INC.Inventors: Libai Xu, Kevin S. McKinny, Cornelis Huiszoon, Christian Stoller