Abstract: An apparatus and method for estimating at least one parameter of interest of an earth formation including an estimation of the parameter of interest using a time-dependent ratio of information obtained from at least one neutron detector through the exposure of the earth formation to a radiation source, particularly a pulsed nuclear source. The apparatus includes a processor and storage subsystem with a program that, when executed, implements the method. Also, an apparatus and method for estimating at least one parameter of interest of an earth formation including an estimation of the parameter of interest using a first component and a second component of an information set obtained using a single radiation detector.

Abstract: The present disclosure relates to borehole logging methods and apparatuses for estimating formation properties using nuclear radiation, particularly an apparatus and method for estimating a formation lithology parameter. The method may include using gamma ray count or count rate information to estimate a formation lithology parameter that may be one of, but not limited to: Z2/A, bulk density, Z2*bulk density/A, linear attenuation coefficients, and porosity. The method may include using time-dependent ratios with a pulsed radiation source. The method may also include dividing gamma ray information by time and/or by energy window. The apparatus includes a processor and storage subsystem with a program that, when executed, implements the method.

Abstract: An apparatus and method for estimating at least one parameter of interest of an earth formation including an estimation of the parameter of interest using a time-dependent ratio of information obtained from at least one neutron detector through the exposure of the earth formation to a radiation source, particularly a pulsed nuclear source. The apparatus includes a processor and storage subsystem with a program that, when executed, implements the method. Also, an apparatus and method for estimating at least one parameter of interest of an earth formation including an estimation of the parameter of interest using a first component and a second component of an information set obtained using a single radiation detector.

Abstract: The present disclosure relates to borehole logging methods and apparatuses for estimating formation properties using nuclear radiation, particularly an apparatus and method for estimating bulk density of a formation. The method may include using gamma ray count rate information to model bulk density. The method may include using time-dependent ratios with a pulsed radiation source. The method may also include dividing gamma ray information by time and/or by energy window. The apparatus includes a processor and storage subsystem with a program that, when executed, implements the method.

Abstract: 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.

Abstract: An apparatus and method for estimating at least one parameter of interest of an earth formation including an estimation of the parameter of interest using a time-dependent ratio of information obtained from at least one neutron detector through the exposure of the earth formation to a radiation source, particularly a pulsed nuclear source. The apparatus includes a processor and storage subsystem with a program that, when executed, implements the method. Also, an apparatus and method for estimating at least one parameter of interest of an earth formation including an estimation of the parameter of interest using a first component and a second component of an information set obtained using a single radiation detector.

Abstract: The present disclosure relates to borehole logging methods and apparatuses for estimating formation properties using nuclear radiation, particularly an apparatus and method for estimating a formation lithology parameter. The method may include using gamma ray count or count rate information to estimate a formation lithology parameter that may be one of, but not limited to: Z2/A, bulk density, Z2*bulk density/A, linear attenuation coefficients, and porosity. The method may include using time-dependent ratios with a pulsed radiation source. The method may also include dividing gamma ray information by time and/or by energy window. The apparatus includes a processor and storage subsystem with a program that, when executed, implements the method.

Abstract: The present disclosure relates to borehole logging methods and apparatuses for estimating formation properties using nuclear radiation, particularly an apparatus and method for estimating bulk density of a formation. The method may include using gamma ray count rate information to model bulk density. The method may include using time-dependent ratios with a pulsed radiation source. The method may also include dividing gamma ray information by time and/or by energy window. The apparatus includes a processor and storage subsystem with a program that, when executed, implements the method.

Abstract: An apparatus and method for estimating at least one parameter of interest of an earth formation including an estimation of the parameter of interest using a time-dependent ratio of information obtained from at least one neutron detector through the exposure of the earth formation to a radiation source, particularly a pulsed nuclear source. The apparatus includes a processor and storage subsystem with a program that, when executed, implements the method. Also, an apparatus and method for estimating at least one parameter of interest of an earth formation including an estimation of the parameter of interest using a first component and a second component of an information set obtained using a single radiation detector.

Abstract: 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.

Abstract: An instrument for performing measurements downhole, includes: a neutron source; and a neutron moderating material exhibiting high compressive strength and high performance for moderation and shielding of neutrons, the shielding disposed proximate to the neutron source. A method for fabricating the instrument is provided.

Abstract: An instrument for performing measurements downhole includes: a neutron source; at least one gamma ray detector equipped for discriminating an energy of an incident gamma photon; and an energy calibration target disposed relative to the neutron source and the at least one gamma ray detector. A method and computer program product for calibrating the instrument is provided.