Abstract: Methods and systems for quantitatively determining pack density within a section of a wellbore are disclosed. The method compares acquired pulsed neutron measurements to models of the section having zero pack density and one hundred percent pack density and extrapolates the measured pulsed neutron data between those two extremes to quantitatively determine pack density. The methods and systems allow hydrocarbon saturation and pack density to be determined in a single trip of a pulsed neutron tool.

Abstract: An apparatus for detecting gamma ray (GR) radiation having a plurality of detector cells arranged in an array is disclosed. Each cell includes a housing having an aperture, the housing comprising a GR absorbing material, and a GR detector disposed within the housing such that external gamma rays are received at the GR detector via the aperture. The apertures of each cell are aligned.

Abstract: A well logging instrument including a plurality of detectors having different precisions and accuracies, the more precise detectors generally having lower accuracies. The detectors are responsive to the interaction of radiation from a suitable source on the instrument with earth formations. Outputs from the plurality of detectors are smoothed and combined to provide processed measurements with improved accuracy and precision.

Abstract: An apparatus for detecting gamma ray (GR) radiation having a plurality of detector cells arranged in an array is disclosed. Each cell includes a housing having an aperture, the housing comprising a GR absorbing material, and a GR detector disposed within the housing such that external gamma rays are received at the GR detector via the aperture. The apertures of each cell are aligned.

Abstract: A method, apparatus, and machine-readable medium for evaluating an earth formation having a fluid mixture including oil and water therein. The earth formation is irradiated with a source and radiation resulting from interaction of the radiation with nuclei is measured at at least two detectors. A fluid zone parameter (FZP) indicative of oil saturation is determined and values of the FZP are established for at least two different values of oil saturation. A value of the oil saturation is estimated using the determined value of the FZP and established values of the FZP. The process may be repeated at a plurality of depths and the determined value of the FZP is displayed at the plurality of depths.

Abstract: Data from a string of multiple formation evaluation data sensor are evaluated by an expert system. Based on the analysis, the logging speed is increased if all the sensors justify it, and is reduced if any of the sensors require a reduced logging speed. Alternatively, the sensitive volume of a NMR sensor is altered based on a determination of a fraction of the sensitive volume that includes a borehole fluid. 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.

Abstract: 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.

Abstract: 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.

Abstract: A pulsed neutron tool with three or more detectors is used for making measurements inside casing. The measurements may be used to determine gas saturation at a constant gas pressure, pressure at constant gas saturation, or to determine both gas saturation and gas pressure.

Abstract: A pulsed neutron tool with three or more detectors is used for making measurements inside casing. The measurements may be used to determine gas saturation at a constant gas pressure, pressure at constant gas saturation, or to determine both gas saturation and gas pressure.

Abstract: A pulsed neutron tool with three or more detectors is used for making measurements inside casing. The measurements may be used to determine gas saturation at a constant gas pressure, pressure at constant gas saturation, or to determine both gas saturation and gas pressure.

Abstract: An apparatus for detecting gamma ray (GR) radiation having a plurality of detector cells arranged in an array is disclosed. Each cell includes a housing having an aperture, the housing comprising a GR absorbing material, and a GR detector disposed within the housing such that external gamma rays are received at the GR detector via the aperture. The apertures of each cell are aligned.

Abstract: Data from a string of multiple formation evaluation data sensor are evaluated by an expert system. Based on the analysis, the logging speed is increased if all the sensors justify it, and is reduced if any of the sensors require a reduced logging speed. Alternatively, the sensitive volume of a NMR sensor is altered based on a determination of a fraction of the sensitive volume that includes a borehole fluid.

Abstract: A well logging instrument including a plurality of detectors having different precisions and accuracies, the more precise detectors generally having lower accuracies. The detectors are responsive to the interaction of radiation from a suitable source on the instrument with earth formations. Outputs from the plurality of detectors are smoothed and combined to provide processed measurements with improved accuracy and precision.

Abstract: A pulsed neutron source irradiates an earth formation. The irradiation produces N16 from O16 in a fluid in the borehole, and the gamma rays produced by the subsequent decay of N16 are detected by a plurality of spaced apart detectors. The count rates of the detectors are accumulated over a time sampling interval to produce temporal signals. Processing of the temporal signals using correlation, differentiation and/or semblance techniques is used for determination of the flow velocity of one or more fluids in the borehole.

Abstract: A pulsed neutron source irradiates an earth formation. The irradiation produces N16 from O16 in a fluid in the borehole, and the gamma rays produced by the subsequent decay of N16 are detected by a plurality of spaced apart detectors. The count rates of the detectors are accumulated over a time sampling interval to produce temporal signals. Processing of the temporal signals using correlation, differentiation and/or semblance techniques is used for determination of the flow velocity of one or more fluids in the borehole.

Abstract: Data from a string of multiple formation evaluation data sensor are evaluated. Based on the analysis, the logging speed is increased if all the sensors justify it, and is reduced if any of the sensors require a reduced logging speed.

Abstract: A method for determining a volume fraction of water moving in a predetermined direction along a highly inclined conduit. The method includes measuring a fractional volume of water occupying the conduit at a plurality of locations along the conduit. An oxygen activation velocity of the water flowing in the conduit is determined at a plurality of locations along the conduit. A counting rate of a gamma ray detector used to measure oxygen activation is normalized with respect to the measured fractional volume of water. The normalized count rates of the gamma ray detector are characterized with respect to a relative velocity between the water and the detector. The step of characterizing is performed in portions of the conduit which are sloped so that gravity acts on the water along the predetermined direction. A fraction of the characterized counting rate represented by the oxygen activation counting rates measured along the conduit is determined.

Abstract: This disclosure provides a method for measuring the velocities of water volumes flowing co-directionally in separate conduits nested such as in injection or production well-bores. The method allows an oxygen activation measurement of the velocity of the water flow in the tubing-casing annulus in the presence of water flowing in the tubing string in the same direction. The method allows continuous logging at variable or constant cable velocities or stationary logging. Based on the method of velocity gauging, the method isolates the signal from the annular flow and can produce a continuous log of linear and volumetric annular flow rates with depth.