Abstract: Methods, systems, and devices for evaluating an earth formation intersected by a borehole. Methods may include irradiating the earth formation using a radiation source to provoke radiation from the formation responsive to the irradiation; taking a radiation measurement and thereby generating radiation measurement information by producing light scintillations from a scintillation material responsive to the absorption by the scintillation material of the radiation from the formation and substantial intrinsic radiation of the scintillation material; and estimating a parameter of interest of the earth formation using the radiation measurement information.

Abstract: An apparatus for estimating a property of an earth formation and a borehole fluid includes a carrier configured to be disposed in a borehole, and a pulsed neutron measurement assembly including a pulsed neutron source configured to emit neutrons into the borehole and the earth formation, and a gamma ray detector. The apparatus also includes a fluid density measurement assembly including the gamma ray detector and a gamma ray source configured to irradiate a borehole fluid with gamma rays. The gamma ray detector is positioned relative to the gamma ray source to detect both of: gamma rays resulting from neutron interactions and gamma rays emitted from the borehole fluid in response to irradiation from the gamma ray source. The apparatus further includes a processor configured to differentiate a pulsed neutron gamma ray spectrum associated with the interactions from a density gamma ray spectrum.

Abstract: An apparatus for estimating a property of an earth formation and a borehole fluid includes a carrier configured to be disposed in a borehole, and a pulsed neutron measurement assembly including a pulsed neutron source configured to emit neutrons into the borehole and the earth formation, and a gamma ray detector. The apparatus also includes a fluid density measurement assembly including the gamma ray detector and a gamma ray source configured to irradiate a borehole fluid with gamma rays. The gamma ray detector is positioned relative to the gamma ray source to detect both of: gamma rays resulting from neutron interactions and gamma rays emitted from the borehole fluid in response to irradiation from the gamma ray source. The apparatus further includes a processor configured to differentiate a pulsed neutron gamma ray spectrum associated with the interactions from a density gamma ray spectrum.

Abstract: An apparatus for estimating a property of an earth formation includes a pulsed neutron generator configured to emit a pulse of neutrons, a formation radiation detector configured to detect radiation emitted from the formation due to interactions with the pulse of neutrons, and a neutron generator radiation detector having a crystal structure and configured to detect a radiation particle emitted from the pulsed neutron generator and to provide a location within the neutron radiation detector at which the particle was detected. The crystal structure includes a plurality of detection cells, each detection cell having at least two electrically conducting columns with an applied potential difference such that electrons generated in the crystal structure by interaction with the radiation particle are collected by at least one of the electrically conducting columns to provide detection locations. A processor estimates the property using the detected formation radiation and the detection locations.

Abstract: An apparatus and method for detecting radiation in a borehole intersecting an earth formation. The apparatus may include a neutron sensitive scintillation media and at least one optically transparent neutron absorptive material optically coupled to the media, which may be positioned to prevent incident neutrons from reaching a neutron-shaded surface of the media, and to provide directional sensitivity. The neutron absorptive material may comprise a light guide optically coupled to the neutron sensitive scintillation media. The scintillation media may be disposed within the at least one optically transparent neutron absorptive material, which may be configured to prevent substantially all incident neutrons having an incident neutron energy below a selected energy threshold from reaching the media. The selected energy threshold may be approximately 0.2 eV. A neutron-reflecting material may be disposed within the scintillation media.

Abstract: An apparatus for estimating a property of an earth formation includes a pulsed neutron generator configured to emit a pulse of neutrons, a formation radiation detector configured to detect radiation emitted from the formation due to interactions with the pulse of neutrons, and a neutron generator radiation detector having a crystal structure and configured to detect a radiation particle emitted from the pulsed neutron generator and to provide a location within the neutron radiation detector at which the particle was detected. The crystal structure includes a plurality of detection cells, each detection cell having at least two electrically conducting columns with an applied potential difference such that electrons generated in the crystal structure by interaction with the radiation particle are collected by at least one of the electrically conducting columns to provide detection locations. A processor estimates the property using the detected formation radiation and the detection locations.

Abstract: Method and apparatus for evaluating an earth formation using at least one detector with a pulsed neutron source that includes a beam of deuterium ions that can be directed to a selected position on a target including tritium that extends axially along a sealed tube. This makes it possible to generate pulsed neutrons from a plurality of positions.

Abstract: An apparatus and method for detecting radiation in a borehole intersecting an earth formation. The apparatus may include a neutron sensitive scintillation media and at least one optically transparent neutron absorptive material optically coupled to the media, which may be positioned to prevent incident neutrons from reaching a neutron-shaded surface of the media, and to provide directional sensitivity. The neutron absorptive material may comprise a light guide optically coupled to the neutron sensitive scintillation media. The scintillation media may be disposed within the at least one optically transparent neutron absorptive material, which may be configured to prevent substantially all incident neutrons having an incident neutron energy below a selected energy threshold from reaching the media. The selected energy threshold may be approximately 0.2 eV. A neutron-reflecting material may be disposed within the scintillation media.

Abstract: Method and apparatus for evaluating an earth formation using a pulsed neutron source comprising of dual beams of oppositely directed hydrogen isotopic ions with timing and focal characteristics of each beam set to accomplish a beam-to-beam focusing interaction to a selected position that extends axially along a sealed tube. This makes it possible to generate pulsed neutrons from a plurality of positions.

Abstract: Method and apparatus for evaluating an earth formation using a pulsed neutron source comprising of dual beams of oppositely directed hydrogen isotopic ions with timing and focal characteristics of each beam set to accomplish a beam-to-beam focusing interaction to a selected position that extends axially along a sealed tube. This makes it possible to generate pulsed neutrons from a plurality of positions.

Abstract: Method and apparatus for evaluating an earth formation using at least one detector with a pulsed neutron source that includes a beam of deuterium ions that can be directed to a selected position on a target including tritium that extends axially along a sealed tube. This makes it possible to generate pulsed neutrons from a plurality of positions.

Abstract: An apparatus for performing an operation in a borehole penetrating the earth, the apparatus having: a carrier configured for conveyance through the borehole; and a neutron source disposed at the carrier and configured to produce a nuclear fusion reaction that emits a neutron to perform the operation.