Abstract: A method for well integrity assessment using machine-trained prediction of physical characteristics related to well integrity across a depth interval of a cased wellbore having one or more casing strings. The method includes collecting scattered X-ray signals from a plurality of X-ray detectors arranged within a well logging tool, learning trained weights to predict wellbore characteristics from the scattered X-ray signals, collecting further scattered X-ray signals from the X-ray detectors, using the trained weights to quantitatively predict the wellbore characteristics from the further X-ray signals, and using the predicted wellbore characteristics to assess well integrity.

Abstract: A neutron porosity tool having an electronic neutron generator arrangement and a control mechanism used to provide voltage and pulses to an electronic neutron tube is provided, the neutron generator arrangement including: at least one vacuum tube; at least one ion target; at least one radio-frequency cavity; at least one high-voltage generator; at least two neutron detectors; at least one pulser circuit; and at least one control circuit. A method of controlling a neutron porosity tool having an electronic neutron generator arrangement and a control mechanism that provides voltage, and pulses to an electronic neutron tube, the method including at least: controlling a bipolar neutron tube to produce two distinct neutron reactions; using a control circuit to modify the output of a pulser circuit; and using a plurality of neutron detectors to determine formation response offsets.

Abstract: Methods and means for reduced ng the overall diameter of an x-ray tube by recessing the vacuum pumping port stub within the ground plane of the x-ray tube without adversely affecting the electrostatic fields within the vacuum tube itself are provided. In one embodiment, x-ray tubes of smaller diameter, which can be used within the highly confined diameters typically found within the pressure housings of borehole tools are used.

Abstract: An x-ray based litho-density tool for measurement of formation surrounding a borehole is provided, the tool including at least an internal length comprising a sonde section, wherein said sonde section further comprises an x-ray source; at least one radiation measuring detector; at least one source monitoring detector; a plurality of sonde-dependent electronics; and a reference detector, wherein the reference detector is used to monitor the output of the x-ray source such that the reference detector's output effects corrections to the outputs of the detectors used to measure the density of the materials surrounding the borehole in order to correct for variations in the x-ray source output. Tool logic electronics, PSUs, and one or more detectors used to measure borehole standoff such that other detector responses maybe compensated for tool standoff are also provided. Shielding, through-wiring; wear-pads that improve the efficacy and tool functionality are also described and claimed.

Abstract: An x-ray-based borehole fluid evaluation tool for evaluating the characteristics of a fluid located external to said tool in a borehole using x-ray backscatter imaging is disclosed, the tool including at least an x-ray source; a radiation shield to define the output faun of the produced x-rays into the borehole fluid outside of the tool housing; at least one collimated imaging detector to record x-ray backscatter images; sonde-dependent electronics; and a plurality of tool logic electronics and power supply units. A method of using an x-ray-based borehole fluid evaluation tool to evaluate the characteristics of a fluid through x-ray backscatter imaging is also disclosed, the method including at least producing x-rays in a shaped output; measuring the intensity of backscatter x-rays returning from the fluid to each pixel of one or more array imaging detectors; and converting intensity data from said pixels into characteristics of the wellbore fluids.

Abstract: An x-ray based cement evaluation tool for measurement of the density of material volumes within single, dual and multiple-casing wellbore environments is provided, wherein the tool uses x-rays to illuminate the formation surrounding a borehole, and a plurality of detectors are used to directly measure the density of the cement annuli and any variations in density within The tool uses x-rays to illuminate the casing surrounding a borehole and a plurality of multi-pixel imaging detectors directly measure the thickness of the casing The tool includes an internal length having a sonde section, wherein the sonde section further includes an x-ray source; a radiation shield for radiation measuring detectors; sonde-dependent electronics; and a plurality of tool logic electronics and PSUs. Other systems and subsystems appropriate for carrying out the foregoing are also disclosed, as are a plurality of example methods of use therefor.

Abstract: An x-ray-based cement evaluation tool for determining whether a cement bond exists between the casing and cement of a cemented borehole is provided, the tool including at least: an internal length comprising a sonde section, wherein said sonde section further comprises an x-ray source; a radiation shield for radiation measuring detectors; arrayed pixelated detectors; sonde-dependent electronics; and a plurality of tool logic electronics and PSUs. A method of using an x-ray-based cement evaluation tool for measuring a cement bond between a casing and the cement of a cemented borehole is also provided, the method including: producing x-ray in a conical beam to illuminate a well casing; measurement of the returning photons as a function of radial and axial offset; remapping the intensity of returning photons to a geometric response within the casing and cement; and determining whether an annulus is present between the casing and cement.

Abstract: An x-ray based litho-density tool for measurement of formation surrounding a borehole is provided, the tool including at least an internal length comprising a sonde section, wherein said sonde section further comprises an x-ray source; at least one radiation measuring detector; at least one source monitoring detector; a plurality of sonde-dependent electronics; and a reference detector, wherein the reference detector is used to monitor the output of the x-ray source such that the reference detector's output effects corrections to the outputs of the detectors used to measure the density of the materials surrounding the borehole in order to correct for variations in the x-ray source output. Tool logic electronics, PSUs, and one or more detectors used to measure borehole standoff such that other detector responses may be compensated for tool standoff are also provided. Shielding, through-wiring, wear-pads that improve the efficacy and tool functionality are also described and claimed.

Abstract: A first example azimuthal neutron porosity tool for imaging formation and cement volumes surrounding a borehole is provided, the tool including at least an internal length comprising a sonde section, wherein said sonde section further comprises one sonde-dependent electronics; a slip-ring and motor section; and a plurality of tool logic electronics and PSUs. An alternative azimuthal neutron porosity tool for imaging formation and cement volumes surrounding a borehole is also provided, the tool including at least a far space detector; a near space detector; and a source located within a moderator shield that rotates around an internal tool axis.

Abstract: An x-ray-based borehole fluid evaluation tool for evaluating the characteristics of a fluid located external to said tool in a borehole using x-ray backscatter imaging is disclosed, the tool including at least an x-ray source; a radiation shield to define the output faun of the produced x-rays into the borehole fluid outside of the tool housing; at least one collimated imaging detector to record x-ray backscatter images; sonde-dependent electronics; and a plurality of tool logic electronics and power supply units. A method of using an x-ray-based borehole fluid evaluation tool to evaluate the characteristics of a fluid through x-ray backscatter imaging is also disclosed, the method including at least producing x-rays in a shaped output; measuring the intensity of backscatter x-rays returning from the fluid to each pixel of one or more array imaging detectors; and converting intensity data from said pixels into characteristics of the wellbore fluids.

Abstract: An x-ray based cement evaluation tool for measurement of the density of material volumes within single, dual and multiple-casing wellbore environments is provided, the tool including at least an internal length comprising a sonde section, wherein said sonde section further comprises an x-ray source; a radiation shield for radiation measuring detectors; sonde-dependent electronics; and a plurality of tool logic electronics and PSUs, wherein the tool uses x-rays to illuminate the formation surrounding a borehole and a plurality of detectors are used to directly measure the density of the cement annuli and any variations in density within. Detectors used to measure casing standoff such that other detector responses are compensated for tool stand-off and centralization; a plurality of reference detectors is used to monitor the output of the x-ray source, and a shortest-axial offset detector is configured to distribute incoming photons into energy classifications such that photoelectric measurements may be made.

Abstract: An x-ray based cement evaluation tool for measurement of the density of material volumes within single, dual and multiple-casing wellbore environments is provided, wherein the tool uses x-rays to illuminate the formation surrounding a borehole, and a plurality of detectors are used to directly measure the density of the cement annuli and any variations in density within The tool uses x-rays to illuminate the casing surrounding a borehole and a plurality of multi-pixel imaging detectors directly measure the thickness of the casing The tool includes an internal length having a sonde section, wherein the sonde section further includes an x-ray source; a radiation shield for radiation measuring detectors; sonde-dependent electronics; and a plurality of tool logic electronics and PSUs. Other systems and subsystems appropriate for carrying out the foregoing are also disclosed, as are a plurality of example methods of use therefor.

Abstract: A thermal control and electrical connection means for an electronic radiation source that provides a cooling and electrical connection to an electronic radiation source in high-temperature environment is provided, including at least a means for physically dislocating a positive high-voltage generator from the anode/target of the x-ray source; a means for conveying coolant fluids to a target anode along a coaxially formed connector; and a means for removing heat from the target anode along a coaxially-formed connector. A method of removing thermal energy from the target of an electronic radiation source is also provided, including at least introducing coolant fluids onto the target; removing coolant fluids from the target; and relocating the coolant fluids to another part of the tool for disposal within the wellbore.

Abstract: An x-ray-based cased wellbore environment imaging tool is provided, the tool including at least an x-ray source; a radiation shield to define the output form of the produced x-rays; a direction controllable two-dimensional per-pixel collimated imaging detector array; sonde-dependent electronics; and a plurality of tool logic electronics and PSUs. A method of using an x-ray-based cased wellbore environment imaging tool to monitor and determine the integrity of materials within wellbore environments is also provided, the method including at least: producing x-rays in a shaped output; measuring the intensity of backscatter x-rays returning from materials surrounding the wellbore; controlling two-dimensional per-pixel collimated imaging detector arrays; and converting image data from said detectors into consolidated images of the wellbore materials.

Abstract: An x-ray-based casing imaging tool, defined by a combination of source collimators, located cylindrically around an X-ray source and a rotatable two-dimensional per-pixel collimated imaging detector array, is provided, the tool including at least an x-ray source; a radiation shield to define the output form of produced x-rays; a direction controllable two-dimensional per-pixel collimated imaging detector array; an imaging window within the tool housing that reduces attenuation of x-rays passing through said tool housing; sonde-dependent electronics; and a plurality of tool logic electronics and PSUs.

Abstract: An x-ray-based reservoir evaluation tool for the measurement of the shale density anticipated at shale-creep barrier within a cased borehole is disclosed, wherein the tool includes an internal length comprising a sonde section, wherein the sonde section further includes an x-ray source; a plurality of radiation measuring detectors; sonde-dependent electronics; and a plurality of tool logic electronics and PSUs. A method of using an x-ray-based shale-seal evaluation tool for measuring the shale density anticipated at shale-creep barrier within a cased borehole is also disclosed, the method including: using x-rays to illuminate the formation surrounding the cased borehole; using detectors to directly measure the density of the formation; using detectors to directly measure the effects on the measurement from tool stand-off or production liner attenuation; and compensating for the production liner and liner-annular region when computing the saturated formation density within the production interval.

Abstract: An x-ray based litho-density tool for measurement of formation surrounding a borehole is provided, the tool including at least an internal length comprising a sonde section, wherein said sonde section further comprises an x-ray source; at least one radiation measuring detector; at least one source monitoring detector; a plurality of sonde-dependent electronics; and a reference detector, wherein the reference detector is used to monitor the output of the x-ray source such that the reference detector's output effects corrections to the outputs of the detectors used to measure the density of the materials surrounding the borehole in order to correct for variations in the x-ray source output. Tool logic electronics, PSUs, and one or more detectors used to measure borehole standoff such that other detector responses may be compensated for tool standoff are also provided. Shielding, through-wiring, wear-pads that improve the efficacy and tool functionality are also described and claimed.

Abstract: A first example azimuthal neutron porosity tool for imaging formation and cement volumes surrounding a borehole is provided, the tool including at least an internal length comprising a sonde section, wherein said sonde section further comprises one sonde-dependent electronics; a slip-ring and motor section; and a plurality of tool logic electronics and PSUs. An alternative azimuthal neutron porosity tool for imaging formation and cement volumes surrounding a borehole is also provided, the tool including at least a far space detector; a near space detector; and a source located within a moderator shield that rotates around an internal tool axis.

Abstract: A control mechanism for a high-voltage generator that provides voltage and current to an electronic radiation source in a high-temperature environment is provided, the control mechanism including at least an intermediate enveloping ground plane, and a ground-plane potential monitoring system that provides an input to a control processor that in turn drives the high-voltage generator. A method of controlling a high-voltage generator that powers an electronic radiation source is also provided, the method including at least: measuring an enveloping ground plane potential such that a change in the potential of said enveloping ground plane surrounding the generator is monitored and used to determine the beginning of one or more of a partial discharge and flash-over event.

Abstract: A borehole fracture evaluation tool for imaging radiation emitted by radioactive materials injected into the formation during hydraulic fracturing operations, the tool including at least one collimated imaging detector used to record x-ray backscatter images; sonde-dependent electronics; and a plurality of tool logic electronics and power supply units. A method for fracture evaluation imaging, the method including at least injecting radioactive tracer materials into the formation fractures; controlling the imaging direction of an imaging array detector; imaging the fracture structures; creating a composite image of the fractures versus the formation; and determining the size and position of the fractures.