Abstract: A method for estimating at least one geological constituent may include obtaining a measured energy spectrum for the at least one geological constituent for a first borehole configuration, generating a calculated energy spectrum for the at least one geological constituent for the first borehole configuration, and generating a calculated energy spectrum for the at least one geological constituent for a second borehole configuration different than the first borehole configuration. The method may further include determining a relationship between the calculated energy spectra for the first and second borehole configurations, and generating an estimated energy spectrum for the at least one geological constituent for the second borehole configuration based upon the measured energy spectrum and the relationship between the calculated energy spectra for the first and second borehole configurations.

Abstract: A method for improving precision of measurement of material composition of formations determined by gamma ray spectral an analysis includes determining an accurate value of an amount of a selected by analyzing a spectrum of gamma rays detected from the formations using a technique that directly relates the gamma ray spectrum to the amount of the material. A precise value of the amount of the material is determined by analyzing the spectrum of detected gamma rays that indirectly relates the gamma ray spectrum to the amount of the material. A function relating the accurate value to the precise value over a selected axial interval along the wellbore is determined. The function is applied to the accurate value at at least one selected axial position along the wellbore to determine an accurate and precise value of the amount of the material.

Abstract: The accurate determination of formation hydrocarbon or water saturation is a useful step in the petrophysical evaluation of petroleum reservoirs. This disclosure presents a new method for estimating hydrocarbon saturation directly from a porosity log and a total organic carbon (TOC) log. The method is enabled by the recent development of a geochemical spectroscopy logging tool that combines inelastic and capture gamma ray measurements to provide a robust and accurate TOC log. The method differs from the prior approach of using carbon-to-oxygen ratios that is most often applied in cased hole evaluation. The main advantages of this method are that it does not use knowledge of formation water resistivity, it does not rely on a resistivity model, it does not use an extensive calibration database, and it is largely independent of clay or other lithology effects.

Abstract: A method of analyzing a geologic formation having a borehole therein may include operating at least one tool within the borehole to collect respective borehole dimensions at different depths in the borehole, and collect respective total values for a given element at the different depths in the borehole. Each total value may be based upon both a value for an adjacent portion of the geologic formation and a value for material within the borehole. The method may also include determining each value of the given element in the adjacent portion of the geologic formation based upon the total value and the corresponding borehole dimensions.

Abstract: Composition-matched downhole tools and methods for using such tools are provided. One such method includes emitting neutrons using a neutron source in the downhole tool to generate formation gamma rays in a surrounding formation. At the same time, however, some of the neutrons may interact with different parts of the downhole tool to form tool gamma rays. The gamma ray spectra of at least some of the formation gamma rays and the tool gamma rays may be detected using a gamma ray detector. The tool gamma rays from the different parts of the tool may have a substantially similar spectral shape. As such, a processor may be used to analyze the spectra of the tool gamma rays using a single tool background standard, thereby simplifying the analysis and improving the precision of the results.

Abstract: 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.

Abstract: 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.

Abstract: A method for correcting detected gamma ray spectra for the effects of energy analyzer pileup includes assigning detected gamma rays to channels in a multichannel analyzer (MCA). A pileup spectrum is estimated. The pileup spectrum is subtracted from the measured spectrum. The result thereof is compared to the preceding estimated pileup free spectrum and the estimating the pileup spectrum, subtracting the pileup spectrum and comparing is repeated until the difference between successive estimates of the pileup-free spectrum falls below a selected threshold.

Abstract: 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.

Abstract: Methods and systems are described for using pulsed neutron ?-ray spectroscopy to measure formation water salinity from within a bore-hole. Through generating a cross-plot of database values of ratios of spectroscopically determined yields of hydrogen (H) and chlorine (Cl) from two detectors, deriving apparent salinities therefrom, formation and borehole water salinities can be determined.

Abstract: The present invention provides systems and methods capable of improving the efficiency and effectiveness of leaching operations. In one embodiment, the present invention may utilize a coiled tubing directional drilling system capable of treating interior portions of the heap/formation. In one embodiment, the present invention may utilize a system and method capable of capturing real time temperature and resistivity data pertaining to pregnant solution characteristics in the heap/formation. In one embodiment, the present invention may utilize one or more wire line deployed X-Ray Fluorescence (XRF) spectrometers capable of quantitatively measuring concentrations of desired metals in the heap/formation during leaching operations. In one embodiment, the present invention utilizes multiple passes of elemental capture spectroscopy logs acquired at regular time intervals to monitor metal concentrations during leaching operations.

Abstract: 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.

Abstract: A method for correcting detected gamma ray spectra for the effects of energy analyzer pileup includes assigning detected gamma rays to channels in a multichannel analyzer (MCA). A pileup spectrum is estimated. The pileup spectrum is subtracted from the measured spectrum. The result thereof is compared to the preceding estimated pileup free spectrum and the estimating the pileup spectrum, subtracting the pileup spectrum and comparing is repeated until the difference between successive estimates of the pileup-free spectrum falls below a selected threshold.

Abstract: 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.

Abstract: 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.

Abstract: Methods and related systems are described for the detection of nuclear radiation. The system can include a scintillator material that intrinsically generates radiation and a photodetection system coupled to the scintillator material and adapted to generate electrical signals based on light emitted from the scintillator material. A processing system adapted and programmed to receive the electrical signals, to generate a count rate reference value based at least in part on electrical signals generated in response to the light emitted from the scintillator material due to the intrinsically generated radiation.

Abstract: Methods and related systems are described for the detection of nuclear radiation. The system can include a tool body adapted to be deployed in a wellbore and a scintillator material that intrinsically generates radiation. The scintillator material is mounted within the tool body. A photodetection system is coupled to the scintillator material, and mounted within the tool body. Features in a spectrum associated with a scintillation material's intrinsic radioactive decay are used for the determination of one or more parameter's of the response function of the radiation detector system.

Abstract: 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.

Abstract: 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.

Abstract: Methods and related systems are described for the detection of nuclear radiation. The system can include a scintillator material that intrinsically generates radiation and a photodetection system coupled to the scintillator material and adapted to generate electrical signals based on light emitted from the scintillator material. A processing system adapted and programmed to receive the electrical signals, to generate a count rate reference value based at least in part on electrical signals generated in response to the light emitted from the scintillator material due to the intrinsically generated radiation.