| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 250269600 | Having neutron source and gamma detector | 38 |
| 20080308720 | Use of Elemental Pulse Neutron Spectroscopy Measurements for Indexing Bitumen Viscosity in the Well - Elemental analysis of an earth formation is obtained using measurements from a gamma ray logging tool. From the elemental analysis, an estimate of the carbon content and the sulfur, vanadium, nickel, titanium and/or molybdenum content of the formation is determined. A table look-up is used to estimate the viscosity from the elemental composition. | 12-18-2008 |
| 20090114806 | Azimuthal Elemental Imaging - Measurements made by a natural gamma ray tool are used to provide an elemental composition of an earth formation. Additional measurements made with a pulsed neutron tool with two or more gamma ray detectors are used to provide a mineralogical and/or elemental image of the formation. This may be used in reservoir navigation and in furthering the understanding of the geology of the prospect. | 05-07-2009 |
| 20090242746 | INELASTIC BACKGROUND CORRECTION FOR A PULSED-NEUTRON INSTRUMENT - A method for correcting data collected with a neutron emitting instrument, includes: obtaining characterization data for the instrument, the characterization data including inelastic background data of the instrument; and correcting the collected data according to the characterization data. A computer program product and an instrument are provided. | 10-01-2009 |
| 20100019138 | NUCLEAR LOGGING TOOL - Nuclear logging tool. At least some of the illustrative embodiments are methods comprising placing a logging tool within a borehole proximate to an earth formation, releasing energetic neutrons from the logging tool, and receiving (at a detector within the logging tool) gamma returns indicative of interactions of the neutrons with elements of the logging tool and elements of the formation, and the gammas indicative of neutron interactions with elements of the logging tool are substantially free from gammas indicative of interactions with iron atoms. | 01-28-2010 |
| 20100193676 | DETERMINING FORMATION CHARACTERISTICS - In some embodiments, apparatus and systems, as well as methods, may operate to irradiate a portion of a geological formation ( | 08-05-2010 |
| 20100224773 | METHOD AND SYSTEM FOR CALCULATING EXTENT OF A FORMATION TREATMENT MATERIAL IN A FORMATION - A method and system for calculating extent of a formation treatment material in a formation. At least some of the illustrative embodiments are methods comprising releasing neutrons into a formation from a neutron source of a logging tool within a borehole having an axis, sensing energies of gammas produced by materials in the formation, the sensing by a gamma detector on the logging tool, generating a measured spectrum of the energies of the gammas sensed by the gamma detector, determining elemental concentrations of materials in the formation based on a basis spectrum, and calculating axial extent of a formation treatment material in the formation in relation to the axis of the borehole based on the elemental concentrations of at least some materials in the formation. | 09-09-2010 |
| 20100327154 | METHODS FOR CALIBRATION OF PULSED NEUTRON LOGGING - A method for logging a subsurface formation includes acquiring neutron capture data using a pulsed neutron tool at a plurality of locations along a borehole penetrating the subsurface formation, wherein the plurality of locations include a formation zone that contains water; comparing an apparent water salinity or an apparent water sigma value estimated from the neutron capture data acquired in the formation zone that contains water with a water salinity or water sigma value of a water sample from the subsurface formation to produce a calibration parameter for the neutron capture data; and correcting the neutron capture data, based on the calibration parameter, to produce corrected neutron capture data. The method may further include determining a water saturation from the corrected neutron capture data. | 12-30-2010 |
| 20110049345 | SOURCELESS GAMMA RAY PRODUCTION SYSTEM AND METHODS - An apparatus for performing an operation in a borehole penetrating the earth includes a carrier and a neutron source that emits neutrons and is disposed in the carrier. The apparatus also includes a target disposed in the carrier and that produces gamma rays as a result of interactions between neutrons produced by the neutron source and at least one material forming the target. The apparatus also includes a gamma ray detector that detects the gamma rays produced by the target and is disposed in the carrier. | 03-03-2011 |
| 20110204217 | Salt Concentration Logging Systems and Methods - Water salinity and water saturation measurements are enhanced by systems and methods for logging salt concentration in formation fluids. Some tool embodiments augment a neutron porosity logging tool with a gamma ray detector configured to measure the rate at which hydrogen nuclei capture neutrons from a neutron source. The ratio of the hydrogen-capture gamma ray count rate to the neutron flux can be combined with a porosity measurement to derive the salt concentration in the formation fluids. When the salt concentration is further combined with resistivity measurements, the water salinity and water saturation can be derived. Some tool embodiments employ a continuous neutron source, Helium-3 filled neutron detectors, and a gamma ray detector that is the same distance from the source as one of the neutron detectors. | 08-25-2011 |
| 20120080588 | SPECTRAL IDENTIFICATION OF PROPPANT IN SUBTERRANEAN FRACTURE ZONES - Proppant placed in a subterranean fracture zone is detected with a spectral identification method in which capture gamma ray spectra are obtained during a logging run carried out with a logging tool having a neutron emitting source and at least one detector sensitive to thermal neutron capture gamma rays. Capture gamma rays from one or more high thermal neutron cross-section materials in the proppant are distinguished from capture gamma rays produced by thermal neutron capture reactions with other downhole formation and borehole constituents utilizing a spectral processing/deconvolution technique. The capture gammas rays from the high thermal neutron capture cross section material in the proppant are used to identify propped fracture zones either alone or in combination with other proppant identification methods which rely on measuring thermal neutron related count rates and/or thermal neutron capture cross-sections from neutron, compensated neutron, and/or pulsed neutron capture logging tools. | 04-05-2012 |
| 20120126106 | Neutron Detection Using a Shielded Gamma Detector - A tool having a neutron source, a gamma ray detector, and a photomultiplier tube is provided. The gamma ray detector and the photomultiplier tube are at least partially surrounded by a layer of boron. The tool is used to make measurements, and the number of prompt gamma rays emitted by the boron is determined from the measurements. The number of neutrons detected may be inferred using the determined number of prompt gamma rays. The tool may also have a layer of neutron absorbing material different from boron or a layer of heavy metal at least partially surrounding the boron. The tool may be a logging tool used to delineate a porous formation and to determine its porosity. The tool may have a plurality of gamma ray detector/photomultiplier tube pairs and those pairs may be used to determine a formation hydrogen index and/or a borehole hydrogen index. | 05-24-2012 |
| 20130105680 | METHOD AND SYSTEM OF DETERMINING A PARAMETER ASSOCIATED WITH A FORMATION CORRECTED FOR NEUTRONS PRODUCED | 05-02-2013 |
| 20130134304 | METHOD AND APPARATUS FOR GAIN REGULATION IN A GAMMA DETECTOR - Methods and systems to determine and regulate the gain of gamma-ray detectors in tools equipped with neutron sources are provided. Gain regulation may be based on the gamma ray background generated in the tool by interaction of neutrons with the nuclei of some elements constituting the tool structure. Some chemical elements that are used in construction of the tool's mechanical parts and structure result in characteristic gamma ray lines in a measured energy spectrum. These lines can be used to calibrate the energy scale of the response of the detector, without any added calibration radio isotopic source. | 05-30-2013 |
| 20130234012 | PULSE NEUTRON FORMATION GAS IDENTIFICATION WITH LWD MEASUREMENTS - Systems, methods, and devices for quantatively identifying gas zones irrespective of porosity or lithology using nuclear downhole tools are provided. In particular, because some formation materials such as shales can confound some conventional measurements, a gas detection measurement may be obtained that can be used to qualitatively identify gas zones. The as detection measurement may be based at least partly on a relationship between inelastic gamma rays, neutron capture gamma rays, and experimental or modeled formation data, such that the gas detection measurement qualitatively indicates a gas zone when a gas zone is present in a formation irrespective of a lithology or a porosity of the formation. | 09-12-2013 |
| 20140001350 | Gas Detection And Quantification Method Using A Pulsed Neutron Logging Tool | 01-02-2014 |
| 20140138529 | Environmental Corrections in Nuclear Spectroscopy Using Variable Element Ratio - A method for estimating an aspect of a formation using a nuclear spectroscopy tool includes placing a nuclear spectroscopy tool into a borehole and emitting neutrons such that some of the neutrons generate gamma rays from a formation adjacent the nuclear spectroscopy tool and some of the neutrons generate gamma rays from elements within the nuclear spectroscopy tool. An energy spectrum of gamma rays induced by the emitted neutrons can be detected. The energy spectrum includes a background having a plurality of measured spectral components. A background ratio between at least one spectral component of the background and another measured spectral component can be determined or estimated in accordance with environmental measurements. The detected gamma ray spectra can be analyzed using a combination of standard spectra and subtracting at least one spectral component of the background in accordance with the background ratio. | 05-22-2014 |
| 20140138530 | Environmental Corrections in Nuclear Spectroscopy Using Variable Shape Standard - An aspect of a formation may be estimated by placing a nuclear spectroscopy tool including a neutron source and a gamma ray detector into a borehole and performing a plurality of environmental measurements. Neutrons are emitted from the nuclear spectroscopy tool such that some of the neutrons generate gamma rays from a formation adjacent the nuclear spectroscopy tool, some of the neutrons generate gamma rays from elements within the nuclear spectroscopy tool and some of the neutrons generate gamma rays from an element in the drilling mud. An energy spectrum of gamma rays induced by the emitted neutrons can be detected with the tool. The detected gamma-ray energy spectrum can be analyzed using a combination of standard spectra, where the shape of at least one of the standard spectra can be varied based on the environmental measurements to account for the environment's effects on gamma-ray spectra. | 05-22-2014 |
| 20140231640 | Nuclear Spectroscopy Corrections Using Multiple Standards and Spatial Regions - A method for estimating an aspect of a formation using a nuclear spectroscopy tool includes placing a nuclear spectroscopy tool including a neutron source and a gamma ray detector into a borehole and performing a plurality of environmental measurements. Neutrons are emitted from the nuclear spectroscopy tool such that some of the neutrons generate gamma rays from a formation adjacent the nuclear spectroscopy tool, some of the neutrons generate gamma rays from elements within the nuclear spectroscopy tool and some of the neutrons generate gamma rays from an element in the drilling mud. An energy spectrum of gamma rays induced by the emitted neutrons can be detected with the tool and analyzed using a combination of standard spectra including at least two sub-standards that represent a common element or group of elements and that are differentiated based on location of neutron interaction, such as where the neutrons thermalize. | 08-21-2014 |
| 20140263998 | Ion Source Having Negatively Biased Extractor - A method of generating ions in a radiation generator includes emitting electrons from an active cathode and on a trajectory away from the active cathode, at least some of the electrons as they travel interacting with an ionizable gas to produce ions. The method also includes setting a potential of at least one extractor downstream of the active cathode such that the ions are attracted toward the at least one extractor. | 09-18-2014 |
| 20150076337 | Gamma-Ray Detectors For Downhole Applications - Methods and related systems are described for gamma-ray detection. A gamma-ray detector is made depending on its properties and how those properties are affected by the data analysis. Desirable properties for a downhole detector include; high temperature operation, reliable/robust packaging, good resolution, high countrate capability, high density, high Z, low radioactive background, low neutron cross-section, high light output, single decay time, efficiency, linearity, size availability, etc. Since no single detector has the optimum of all these properties, a downhole tool design preferably picks the best combination of these in existing detectors, which will optimize the performance of the measurement in the required environment and live with the remaining non-optimum properties. A preferable detector choice is one where the required measurement precision (logging speed) is obtained for all of the required inelastic elements and/or minimization of unwanted background signals that complicate the data analysis. | 03-19-2015 |
| 20150083905 | PULSED NEUTRON TOOL FOR DOWNHOLE OIL TYPING - Methods for determining a value indicative of liquid density of a formation include obtaining an inelastic count rate and a capture count rate of a gamma detector for a particular borehole depth, calculating a ratio of an inelastic count rate to a capture count rate for the particular borehole depth, determining a value indicative of liquid density based on the ratio of the inelastic count rate to the capture count rate for the particular borehole depth, repeating the obtaining, calculating and determining for a plurality of borehole depths, and producing a plot of the value indicative of liquid density of the formation as a function of borehole depth. | 03-26-2015 |
| 20150108339 | PULSED-NEUTRON TOOL METHODS AND SYSTEMS FOR MONITORING CASING CORROSION - Casing condition is an important concern to oilfield operators. Systems and methods are disclosed herein for using neutron logging tools to measure casing condition, using windows in the gamma energy spectrum that are sensitive and insensitive to casing condition to obtain a ratio having a value that ranges between one extreme representative of completely absent casing and an opposite extreme representative of casing in good condition. The sensitive (“divergence”) window may be positioned at or near 7.65 MeV, the characteristic energy of gamma rays from a neutron capture event by an iron nucleus. The insensitive (“consistency”) window is preferably adjacent to the divergence window with a comparable size to the divergence window. A suitable division point between the windows may be about 6.25 MeV. | 04-23-2015 |
| 20160047938 | Correction to Determined Formation Sulfur to Account for Sulfur in the Wellbore - A method for correcting determined sulfur content in formations penetrated by a wellbore for sulfur in the wellbore includes determining an amount of sulfur from spectral analysis of gamma rays detected by a well logging instrument disposed in the wellbore. The gamma rays result from imparting neutrons into the formations. The method includes determining if strontium is present in fluid disposed in the wellbore. An amount of strontium is determined from the spectral analysis. A corrected sulfur content of the formation is determined based on the determined amount of strontium. | 02-18-2016 |
| 250269700 | With plural gamma detectors | 11 |
| 20080251710 | Method and Apparatus for Determining Silicon Content of the Earth Formations in Cased Well Bores - Measurements made with a pulsed neutron source and three or more gamma ray detectors are used to estimate the silicon and oxygen content of earth formations. | 10-16-2008 |
| 20090026359 | METHOD TO SIMULTANEOUSLY DETERMINE PORE HYDROCARBON DENSITY AND WATER SATURATION FROM PULSED NEUTRON MEASURMENTS - A method comprising using inelastic and capture gamma-ray count rates from two detectors in a borehole logging tool and determining formation water saturation. In this method the formation water saturation is determined without prior knowledge of the carbon density in the pore hydrocarbons. | 01-29-2009 |
| 20090114807 | LWD Azimuthal Pulsed Neutron Lithology Imaging Tool - Measurements made by a pulsed neutron tool with two or more gamma ray detectors are used to provide a mineralogical and/or elemental image of the formation. This may be used in reservoir navigation and in furthering the understanding of the geology of the prospect. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b). | 05-07-2009 |
| 20090140134 | Hermetically Sealed Packaging and Neutron Shielding for Scintillation-Type Radiation Detectors - A well logging instrument includes a source of high energy neutrons arranged to bombard a formation surrounding the instrument. A scintillator sensitive to gamma radiation resulting from interaction of the high energy neutrons with the formation is disposed in the instrument. A neutron shielding material surrounds the scintillator. A neutron moderator surrounds the neutron shielding material. An amplifier is optically coupled to the scintillator. | 06-04-2009 |
| 20120068060 | METHOD FOR THROUGH-CASING 3-PHASE SATURATION DETERMINATION - A method for estimating a parameter of interest of an earth formation having a fluid contained in pores of the earth formation, the method includes: conveying a carrier through a borehole penetrating the earth formation; irradiating the earth formation with neutrons from a neutron source disposed at the carrier; measuring radiation emitted from the earth formation resulting from the irradiating using at least one detector; calculating or determining a mathematical parameter from radiation measured by the at least one detector; predicting values of the mathematical parameter over a range of values of an earth formation property; and comparing the mathematical parameter to the predicted values to estimate the parameter of interest. | 03-22-2012 |
| 20120091329 | METHOD FOR HYDROCARBON SATURATION AND HYDRAULIC FRAC PLACEMENT - A method for estimating a property of an earth formation, the method includes: conveying a carrier through a borehole penetrating the earth formation; irradiating the formation with neutrons from a neutron source disposed at the carrier; detecting a first signal from the formation due to the irradiating using a first radiation detector, the first signal being related to a saturation of a fluid in the formation; detecting a second signal from an element in the formation due to the irradiating using a second radiation detector, the second signal being related to an element emitting the second signal in the formation; and estimating the property from the first signal and the second signal. | 04-19-2012 |
| 20120326017 | METHOD OF CALCULATING FORMATION CHARACTERISTICS - A method of calculating a formation characteristic includes measuring with at least two detectors spaced apart from each other an intensity of gamma rays, and calculating the formation characteristic by calculating a ratio of the intensity of the gamma rays detected by the two detectors. | 12-27-2012 |
| 20150090870 | FORMATION IMAGING USING NEUTRON ACTIVATION - A method for determining azimuthal formation information using neutron activation, wherein the formation is activated by a neutron source and the activation signal is measured by at least one detector trailing the neutron source during the logging operation. The number of detected gamma rays as a function of the detector azimuth may be used to provide azimuthal information for determining an image of the formation surrounding the borehole. | 04-02-2015 |
| 20150090871 | DOWNHOLE CEMENT EVALUTION USING PULSED NEUTRON MEASUREMENTS - Estimating cement voids in between a casing and a borehole wall of a borehole penetrating the earth formation includes forming with a computing device an actual ratio of radiation induced by a neutron source and measured by a first detector and a second detector when the tool is at two or more different locations in the borehole. A relationship between the actual ratio and the porosity at each of the two or more different locations is used and compared to two different cases of estimates of the ratio. Based on the comparison, an estimate of the cement voids at the two or more locations. | 04-02-2015 |
| 20150369956 | SYSTEMS, COMPUTER MEDIUM AND COMPUTER-IMPLEMENTED METHODS FOR LOGGING USING A LOGGING TOOL WITH ADJUSTABLE DETECTORS - Provided are embodiments of systems, computer medium and computer-implemented methods for logging using a customizable logging tool. In some embodiments, the logging tool is capable of being disposed in a borehole formed in a geologic formation. The logging tool includes a source for emitting signals into the geologic formation surrounding the borehole and a plurality of detectors for detecting signals generated as a result of emission of signals by the source into the geologic formation surrounding the borehole. The plurality of detectors are independently repositionable such that a source-to-detector spacing for the detectors is independently variable, to provide optimum signal depending on the characteristics of the target reservoir, the borehole, and the tool source and detectors. | 12-24-2015 |
| 20160003969 | Pulsed Neutron Well Logging Method For Determining Multiple Formation Parameters - A method for well logging includes emitting a plurality of bursts of high energy neutrons into a wellbore and formations surrounding the wellbore. During and for a selected duration after at least one of the plurality of bursts, gamma rays are detected at at least one location spaced apart from the emitting and characterizing an energy of the detected gamma rays. After the last burst, gamma rays are detected and energy spectrum and rates of detection with respect to time thereof are determined. The foregoing is repeated for a selected number of times. After the selected number of times background gamma rays are measured. At least one of the numbers of detected gamma rays during a selected time interval and an energy spectrum of the detected gamma rays during the selected time interval is used to determine selected formation properties. | 01-07-2016 |
| 250269800 | With detection in plural consecutive time intervals | 4 |
| 20130048849 | METHODS FOR SOURCELESS DENSITY DOWNHOLE MEASUREMENT USING PULSED NEUTRON GENERATOR - Disclosed is a method for estimating a density of an earth formation penetrated by a borehole. The method includes: emitting a pulse of fast neutrons into the formation during a neutron-pulse time interval; detecting gamma-rays due to inelastic scattering and thermal capture of the emitted neutrons in the formation to provide a gamma-ray energy spectrum due to the inelastic scattering and the thermal capture during a first time interval within the neutron-pulse time interval and to provide a time spectrum of counts or count rates due to thermal capture during a second time interval occurring after the neutron-pulse time interval; determining a macroscopic capture cross section of the formation from a decay in the time spectrum of counts or count rates; determining an elemental weight fraction from the gamma-ray energy spectrum; and estimating the density of the formation using the macroscopic capture cross section and the elemental weight fraction. | 02-28-2013 |
| 20140042311 | Neutron Porosity Based On One Or More Gamma Ray Detectors And A Pulsed Neutron Source - A method for pulsed neutron well logging of a subsurface formation, includes irradiating the formation with a plurality of bursts of neutrons of a group of selected durations; detecting gamma rays resulting from interaction of the neutrons during a group of selected time gates which contains at least some early and late gamma ray counts. The gamma rays are detected at at least two axially spaced apart locations from a position of the irradiating. A weighted sum of the numbers of gamma rays detected in each of the time gates is calculated. A ratio of the weighted sum of detected gamma rays at a first axial spacing to the weighted sum at a second axial spacing is determined. The ratio is used to determine a hydrogen index of the subsurface formation. | 02-13-2014 |
| 20150362618 | Pulsed Neutron Measurement Method And System - A method includes emitting a burst of neutrons having a first duration into earth formations. Neutrons are detected at a first position spaced apart from the emitting in two time intervals following the burst. After a selected delay time, a second duration neutron burst is emitted into the formations. Gamma rays are detected in selected time intervals following the second burst. The detected neutrons in the two time intervals are used to calculate a thermal neutron capture cross section. Gamma rays detected at the first position in following the second duration burst are used to determine an apparent formation thermal neutron capture cross section and to adjust a time interval for each of the first duration, the second duration and the starting time thereof for detecting gamma rays. The estimated wellbore thermal neutron capture cross section is used to determine an apparent formation thermal neutron capture cross section. | 12-17-2015 |
| 20160170079 | Neutron Porosity Based On One Or More Gamma Ray Detectors And A Pulsed Neutron Source | 06-16-2016 |
