Abstract:
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.
Abstract:
Various embodiments include apparatus and methods to detect and locate conductive structures below the earth's surface. Tools can be configured with receiving sensors arranged to receive signals generated from a conductive structure in response to a current flowing on the conductive structure. Magnetic-related values from the signals can be processed, relative to the tool, to determine a position of a conductive structure from which the signal was generated in response to current flowing on the conductive structure. Additional apparatus, systems, and methods are disclosed.
Abstract:
Various resistivity logging tools, systems, and methods are disclosed. At least some system embodiments include a logging tool and at least one processor. The logging tool provides transmitter-receiver coupling measurements that include at least direct coupling along the longitudinal tool axis (Czz), direct coupling along the perpendicular axis (Cxx or Cyy), and cross coupling along the longitudinal and perpendicular axes (Cxz, Cyz, Czx, or Czy). The processor combines a plurality of the coupling measurements to obtain inversion parameters. Based at least in part on the inversion parameter, the processor performs an inversion process to determine a vertical conductivity and, based in part on the vertical conductivity, determines borehole corrected values for said transmitter-receiver coupling measurements. One or more of the borehole corrected values can be provided as a function of borehole position.
Abstract:
Tools, systems, and methods are disclosed for multi-component induction logging with iterative analytical conversion of tool measurements to formation parameters. At least some system embodiments include a logging tool and at least one processor. The logging tool provides transmitter-receiver coupling measurements that include at least diagonal coupling measurements (Hzz, Hxx, and/or Hyy) and cross-coupling measurements (Hxy, Hxz, and Hyz). The processor employs an iterative analytical conversion of the cross-coupling measurements into formation resistive anisotropy and dip information. The processor may further provide one or more logs of the resistive anisotropy and/or dip information.
Abstract:
A system and method for determining formation parameters is provided. The system includes an induction logging tool (102) having a plurality of transmitter coils (Tx, Ty, Tz). The induction logging tool further includes a plurality of receiver coils (Rx, Ry, Rz), each of the receiver coils being spaced apart from the transmitter coils by a predetermined distance and receiving a response signal from the formation (104). The system includes circuitry (114) 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.