Abstract: Various apparatus or methods are arranged to operate a tool downhole in a well, where the tool has a detection package operable to detect gamma rays. Deviation of energy spectra of detected gamma rays in each selected energy window of a set of selected energy windows with respect to reference energy spectra of the respective selected energy window can be detected. One or more properties of one or more regions around the tool can be determined from the deviations, the regions being between the tool and a source of the detected gamma rays in a formation around the well. Additional apparatus, systems, and methods having a gamma ray detection package can operate in a variety of applications.

Abstract: Various embodiments include apparatus and methods to conduct neutron-neutron measurements and to evaluate quality of cement between a casing and a formation. A tool can include a neutron source, a far detector, and a near detector, where the far detector and the near detector detect neutrons in response to activation of the neutron source. Measured counts of the detected neutrons can be compared with respect to expected counts of neutrons. From one or more comparisons, the quality of the cement can be evaluated. Additional apparatus, systems, and methods are disclosed.

Abstract: In some embodiments, a method and apparatus, as well as an article, may operate to estimate a property of an earth formation by generating at least one shale model to represent an earth formation comprised of a non-zero percentage of shale. The shale model includes two curves to represent a relationship between a porosity parameter and a pulsed neutron measurement at two different corresponding percentages of gas saturation, respectively. A matrix model representing an earth formation with 0% shale is combined with one or more shale models to create a formation model. Measured pulsed neutron data is compared with the formation model to estimate a property of the earth formation. Additional apparatus, systems, and methods are disclosed.

Abstract: Determining a value indicative of hydrogen index. At least some of the example embodiments are methods including obtaining an inelastic count rate and a capture count rate of a gamma detector for a particular borehole depth in a formation, calculating a ratio of an inelastic count rate to a capture count rate for the particular borehole depth, and determining a value indicative of hydrogen index based on the ratio of the inelastic count rate to the capture count rate for the particular borehole depth.

Abstract: Various apparatus or methods are arranged to operate a tool downhole in a well, where the tool has a detection package operable to detect gamma rays. Deviation of energy spectra of detected gamma rays in each selected energy window of a set of selected energy windows with respect to reference energy spectra of the respective selected energy window can be detected. One or more properties of one or more regions around the tool can be determined from the deviations, the regions being between the tool and a source of the detected gamma rays in a formation around the well. Additional apparatus, systems, and methods having a gamma ray detection package can operate in a variety of applications.

Abstract: In some embodiments, a method and apparatus, as well as an article, may operate to estimate a property of an earth formation by generating at least one shale model to represent an earth formation comprised of a non-zero percentage of shale. The shale model includes two curves to represent a relationship between a porosity parameter and a pulsed neutron measurement at two different corresponding percentages of gas saturation, respectively. A matrix model representing an earth formation with 0% shale is combined with one or more shale models to create a formation model. Measured pulsed neutron data is compared with the formation model to estimate a property of the earth formation. Additional apparatus, systems, and methods are disclosed.

Abstract: Various embodiments include apparatus and methods to conduct neutron-neutron measurements and to evaluate quality of cement between a casing and a formation. A tool can include a neutron source, a far detector, and a near detector, where the far detector and the near detector detect neutrons in response to activation of the neutron source. Measured counts of the detected neutrons can be compared with respect to expected counts of neutrons. From one or more comparisons, the quality of the cement can be evaluated. Additional apparatus, systems, and methods are disclosed.

Abstract: A switch includes a spring. The switch further includes a collapsing element. The spring has a first state in which it is being held in tension by a restraining element and a second state in which it is not being held in tension because the restraining element has failed. The collapsing element is situated such that when sufficient power is applied to the collapsing element heat from the collapsing element will cause the restraining element to fail. The switch further includes a first contact coupled to the spring. The switch further includes a second contact coupled to the spring. The first contact and the second contact are separate from each other when the spring is in the first state. The first contact and the second contact are electrically connected to each other when the spring is in the second state.

Abstract: An apparatus includes a radiation source to output radiation after power is supplied. The apparatus also includes a power source to supply power. The apparatus includes an ambient-activated switch electrically coupled between the radiation source and the power source. The ambient-activated switch is to switch to an open position while a value for an ambient characteristic for the ambient-activated switch is at an ambient level for a surface of the Earth. The ambient-activated switch is to switch to a closed position while the value for the ambient characteristic for the ambient-activated switch is at a downhole ambient level, wherein the ambient-activated switch is to electrically couple the power source to the radiation source while in the closed position.

Abstract: In some embodiments, an apparatus includes a radiation source to output radiation after power is supplied. The apparatus also includes a power source to supply power. The apparatus includes an ambient-activated switch electrically coupled between the radiation source and the power source. The ambient-activated switch is to switch to an open position while a value for an ambient characteristic for the ambient-activated switch is at an ambient level for a surface of the Earth. The ambient-activated switch is to switch to a closed position while the value for the ambient characteristic for the ambient-activated switch is at a downhole ambient level, wherein the ambient-activated switch is to electrically couple the power source to the radiation source while in the closed position.

Abstract: Determining a value indicative of gas saturation of a formation. At least some of the illustrative embodiments are methods including: obtaining an inelastic count rate and a capture count rate of a gamma detector for a particular borehole depth; removing at least a portion of the chlorine response from the capture count rate, thereby creating a modified capture count rate; calculating a ratio of an inelastic count rate to the modified capture count rate for the particular borehole depth; determining a value indicative of gas saturation based on the ratio; and producing a plot of the value indicative of gas saturation as a function of borehole depth for a formation that the borehole at least partially penetrates.

Abstract: A cable includes a conductor. A plurality of inner armor wires is wrapped around the conductor. At least some of the plurality of inner armor wires have non-circular and non-rectangular cross-sectional shapes. A plurality of outer armor wires are wrapped around the inner armor wires. At least some of the plurality of outer armor wires have non-circular and non-rectangular cross-sectional shapes.

Abstract: Determining a value indicative of hydrogen index. At least some of the example embodiments are methods including obtaining an inelastic count rate and a capture count rate of a gamma detector for a particular borehole depth in a formation, calculating a ratio of an inelastic count rate to a capture count rate for the particular borehole depth, and determining a value indicative of hydrogen index based on the ratio of the inelastic count rate to the capture count rate for the particular borehole depth.

Abstract: An apparatus includes a radiation source to output radiation after power is supplied. The apparatus also includes a power source to supply power. The apparatus includes an ambient-activated switch electrically coupled between the radiation source and the power source. The ambient-activated switch is to switch to an open position while a value for an ambient characteristic for the ambient-activated switch is at an ambient level for a surface of the Earth. The ambient-activated switch is to switch to a closed position while the value for the ambient characteristic for the ambient-activated switch is at a downhole ambient level, wherein the ambient-activated switch is to electrically couple the power source to the radiation source while in the closed position.

Abstract: Determining a value indicative of fracture quality. At least some of the illustrative embodiments are methods including: obtaining or measuring gas saturation of a formation to create a value indicative of pre-fracture gas saturation; and after a fracturing process measuring gas saturation of the formation to create a value indicative of post-fracture gas saturation; and creating a value indicative of fracture quality based on the value indicative of pre-fracture gas saturation and the value indicative of post-fracture gas saturation.

Abstract: An actuation apparatus includes an electronics module (102), an actuator module (104) coupled to the electronics module and electrically communicating with the electronics module, and a motor (112) in the actuator module coupled to a drive member (106), the drive member moveable between a first position and a second position, wherein the movement of the drive member between the first and second positions is adjustable in response to a signal from the electronics module. In some embodiments, the electronics module is operable to adjust a speed of the drive member. The motor may be a brushless direct current motor. In other embodiments, the actuation apparatus (300) includes a processor and a memory, the adjustable drive member is engaged with an actuatable tool (200), the processor receives feedback from the drive member and the tool, and the processor is operable to create a signature in response to the movement of the drive member and compare the signature to a baseline.

Abstract: Determining a value indicative of fracture quality. At least some of the illustrative embodiments are methods including: obtaining or measuring gas saturation of a formation to create a value indicative of pre-fracture gas saturation; and after a fracturing process measuring gas saturation of the formation to create a value indicative of post-fracture gas saturation; and creating a value indicative of fracture quality based on the value indicative of pre-fracture gas saturation and the value indicative of post-fracture gas saturation.

Abstract: Determining a value indicative of gas saturation of a formation. At least some of the illustrative embodiments are methods including: obtaining an inelastic count rate and a capture count rate of a gamma detector for a particular borehole depth; removing at least a portion of the chlorine response from the capture count rate, thereby creating a modified capture count rate; calculating a ratio of an inelastic count rate to the modified capture count rate for the particular borehole depth; determining a value indicative of gas saturation based on the ratio; and producing a plot of the value indicative of gas saturation as a function of borehole depth for a formation that the borehole at least partially penetrates.

Abstract: A switch includes a spring. The switch further includes a collapsing element. The spring has a first state in which it is being held in tension by a restraining element and a second state in which it is not being held in tension because the restraining element has failed. The collapsing element is situated such that when sufficient power is applied to the collapsing element heat from the collapsing element will cause the restraining element to fail. The switch further includes a first contact coupled to the spring. The switch further includes a second contact coupled to the spring. The first contact and the second contact are separate from each other when the spring is in the first state. The first contact and the second contact are electrically connected to each other when the spring is in the second state.

Abstract: An apparatus and method for measuring the conductivity of borehole fluid. Based on the fluid conductivity, the fluid type may also be identified. The apparatus and method can be useful in differentiating between native water and injected water in oil recovery operations. The apparatus and method presented can also be used to calibrate testing and production equipment allowing for more reliable and accurate measurements. The apparatus and method presented can further be used to better characterize water to oil ratio in reservoirs.