Abstract: An imaging tool that includes an array of pads. The array of pads are in communication with a hot terminal of a single phase electrical alternating current power source in communication with the array of pads. The single phase electrical alternating current power source includes two return electrodes. One of the return electrodes is located above the array of pads, and the other return terminal is located below the array of pads.

Abstract: An imaging tool that includes an array of pads. The array of pads are in communication with a hot terminal of a single phase electrical alternating current power source in communication with the array of pads. The single phase electrical alternating current power source includes two return electrodes. One of the return electrodes is located above the array of pads, and the other return terminal is located below the array of pads.

Abstract: A well-logging system may include a tool assembly to be positioned within a borehole of a subterranean formation and to store second data including a second time marker related to a first time marker. The well-logging system may include a controller above the subterranean formation. The controller may process first data including the first time marker, recover the second data, and synchronize the second data based upon the second time marker and the first time marker.

Abstract: An apparatus for logging a formation traversed by a borehole includes a tool adapted for conveyance inside the borehole, a tool bias mechanism comprising a flexible member coupled to a first side of the tool body and adapted to urge a second side of the tool body into contact with a side of the borehole, a sensing pad responsive to a property of the formation, and a pad bias mechanism independent of the tool bias mechanism coupling the sensing pad to the second side of the tool body and adapted to urge the sensing pad into contact with the side of the borehole.

Abstract: An apparatus for logging a formation traversed by a borehole includes a plurality of logging tools adapted for conveyance inside the borehole. The plurality of logging tools includes a tool body, a sensing pad responsive to a density property of the formation coupled to the tool body, a current emitting measure electrode responsive to a lateral resistivity property of the formation incorporated on the sensing pad, a mechanism for urging the sensing pad in contact with a side of the borehole coupled to the tool body, and a pair of mass isolation bands disposed about the tool body to isolate a mass of the tool body adjacent the measure electrode.

Abstract: A borehole caliper tool includes a tool body, a bow spring flexibly coupled to the tool body, a target coupled to the bow spring, and an ultrasonic transducer coupled to the tool body, wherein in operation the ultrasonic transducer transmits an acoustic pulse to the target and receives an echo of the acoustic pulse from the target.

Abstract: A borehole caliper tool includes a tool body and an arm coupled to the tool body. The arm is deflectable relative to the tool body. The caliper tool further includes a cam coupled to the arm such that a position of the cam changes as the arm deflects. The caliper tool further includes a proximity sensor for sensing the position of the cam, wherein the position of the cam provides an indication of the deflection of the arm relative to the tool body.

Abstract: A combined resistivity tool incorporating both induction/propagation antennas and lateral resistivity antennas disposed in recesses of downhole tubulars, in which a lateral resistivity antenna includes an insulating base layer disposed in the recess; a toroidal antenna disposed over the insulating base layer; and a shield disposed over the recess.

Abstract: A method is disclosed for compressing a frame of data representing parameter values, a time at which each parameter value was recorded, and an orientation of a sensor at the time each parameter value was recorded. Generally the method includes performing a two-dimensional transform on the data in the orientation domain and in a domain related to the recording time. In one embodiment, the method includes calculating a logarithm of each parameter value. In one embodiment, the 2-D transform includes generating a Fourier transform of the logarithm of the parameter values in the azimuthal domain, generating a discrete cosine transform of the transform coefficients in the time domain. This embodiment includes quantizing the coefficients of the Fourier transform and the discrete cosine transform. One embodiment of the method is adapted to transmit resistivity measurements made by an LWD instrument in pressure modulation telemetry so that while-drilling images of a wellbore can be generated.