摘要:
Various embodiments include apparatus and methods to make resistivity measurements in a borehole using tool having an array of electrodes operable to provide focused currents, measure corresponding voltages, and measure corresponding voltage differences to determine resistivity. Tools can be configured to operate at a plurality of modes when voltage differences at some frequencies are effectively unreadable. Additional apparatus, systems, and methods are disclosed.
摘要:
Various embodiments include apparatus and methods to make resistivity measurements in a borehole using tool having an array of electrodes operable to provide focused currents, measure corresponding voltages, and measure corresponding voltage differences to determine resistivity. Tools can be configured to operate at a plurality of modes when voltage differences at some frequencies are effectively unreadable. Additional apparatus, systems, and methods are disclosed.
摘要:
Various embodiments include methods and apparatus structured to balance electrode pairs (112, 312) of a tool (105, 305) providing voltage equivalence between the electrode pairs. An electrically conductive wire (113, 313) coupling the electrodes of an electrode pair can be arranged such that resistance of the electrically conductive wire does not adversely affect the voltage equivalence. The electrically conductive wire can also be structured to provide temperature independent balancing by arranging the electrically conductive wire with respect to a measuring node (116, 316). Additional apparatus, systems, and methods are disclosed.
摘要:
Various embodiments include methods and apparatus structured to balance electrode pairs (112, 312) of a tool (105, 305) providing voltage equivalence between the electrode pairs. An electrically conductive wire (113, 313) coupling the electrodes of an electrode pair can be arranged such that resistance of the electrically conductive wire does not adversely affect the voltage equivalence. The electrically conductive wire can also be structured to provide temperature independent balancing by arranging the electrically conductive wire with respect to a measuring node (116, 316). Additional apparatus, systems, and methods are disclosed.
摘要:
In some embodiments, an apparatus and a system, as well as a method and an article, may operate to determine spatial orientations of one or more transmitters attached to a first downhole component, relative to one or more receivers attached to a second downhole component, at common points in time during rotation of the first and the second downhole components. The first downhole component may be variably, rotationally coupled to the second downhole component. Further activity may include transforming raw measurements of transmitter signals provided by the receiver(s) into calibrated measurements based on the spatial orientations at the common points in time. Additional apparatus, systems, and methods are described.
摘要:
In some embodiments, an apparatus and a system, as well as a method and an article, may operate to determine spatial orientations of one or more transmitters attached to a first downhole component, relative to one or more receivers attached to a second downhole component, at common points in time during rotation of the first and the second downhole components. The first downhole component may be variably, rotationally coupled to the second downhole component. Further activity may include transforming raw measurements of transmitter signals provided by the receiver(s) into calibrated measurements based on the spatial orientations at the common points in time. Additional apparatus, systems, and methods are described.
摘要:
A system and method for determining formation parameters is provided. The system includes an induction logging tool having a plurality of transmitter coils. The induction logging tool further includes a plurality of receiver coils, each of the receiver coils being spaced apart from the transmitter coils by a predetermined distance and receiving a response signal from the formation. The system includes circuitry coupled to the induction logging tool, the circuitry determining voltages induced in the plurality of receiver coils by the response signal. The circuitry separates real or in-phase portions of the determined voltages from imaginary of ninety degrees out of phase portions of the determined voltages and determines formation parameters using imaginary portions of the measured voltages.
摘要:
In some embodiments, an apparatus and a system, as well as a method and an article, may operate to receive electromagnetic measurement data characterizing a formation from at least one transmitter-receiver pair. Further activity includes transforming the electromagnetic measurement data into transformed measurement data by computing a wavelet transform over the electromagnetic measurement data to provide wavelet coefficients, removing the wavelet coefficients below a selected threshold to provide remaining coefficients, and synthesizing the transformed measurement data by computing a reverse wavelet transform over a combination of the remaining coefficients. Additional apparatus, systems, and methods are described.
摘要:
A system and method for determining formation parameters is provided. The system includes an induction logging tool having a plurality of transmitter coils. The induction logging tool further includes a plurality of receiver coils, each of the receiver coils being spaced apart from the transmitter coils by a predetermined distance and receiving a response signal from the formation. The system includes circuitry coupled to the induction logging tool, the circuitry determining voltages induced in the plurality of receiver coils by the response signal. The circuitry separates real or in-phase portions of the determined voltages from imaginary of ninety degrees out of phase portions of the determined voltages and determines formation parameters using imaginary portions of the measured voltages.