Abstract: A ground drilling device for cable-guided drilling comprising a drive for connecting and/or moving rod sections of a drill string along a drill string axis, wherein a cable reserve for receiving a cable with a length of at least two rod sections is provided and a contact device for electrical contacting of one end of the cable of the cable reserve is provided.

Abstract: A gap sub uses a plurality of insulating members in conjunction with at least two metallic members to effect a mechanically and electrically robust configuration. The gap sub includes an upper end portion, a lower end portion, an outer sleeve, an inner sleeve, an insulating outer washer, an insulating inner washer, and an insulating spider. The insulating outer washer is configured to transfer a first axial load between the upper end portion and the outer sleeve. The insulating inner washer is configured to transfer a second axial load between the inner sleeve and the lower end portion. The insulating spider is configured to transfer a torsional load between outer sleeve and the inner sleeve.

Abstract: Methods and systems for acquiring data in a wellbore. The method includes deploying an instrument connected to an instrument line into a drill string, through a sealed entry port formed in a drilling device coupled to the drill string, the drill string being at least partially within the wellbore, the wellbore penetrating a subterranean formation. The method also includes transmitting a signal from a source and through the formation. The signal is sensed by the instrument in the drill string. The method further includes determining one or more formation characteristics based on the signal sensed by the instrument, and performing one or more drilling processes using the drill string, while transmitting the signal, determining the one or more formation characteristics, or both.

Abstract: Methods and systems for acquiring data in a wellbore. The method includes deploying an instrument connected to an instrument line into a drill string, through a sealed entry port formed in a drilling device coupled to the drill string, the drill string being at least partially within the wellbore, the wellbore penetrating a subterranean formation. The method also includes transmitting a signal from a source and through the formation. The signal is sensed by the instrument in the drill string. The method further includes determining one or more formation characteristics based on the signal sensed by the instrument, and performing one or more drilling processes using the drill string, while transmitting the signal, determining the one or more formation characteristics, or both.

Abstract: A method for manufacturing a system for drilling includes receiving a drive shaft for transmitting a torque to a downhole tool and forming a hollow central passage in a tubular wall of the drive shaft extending along a longitudinal axis L. The hollow central passage allows a flow of a drilling fluid through a bearing section of the system. The method further includes disposing an elongated flow diverter in the tubular wall of the drive shaft. The elongated flow diverter has a body that includes axially-spaced apertures distributed along the longitudinal axis L of the drive shaft and the hollow central passage. The distribution of the apertures along the longitudinal axis L reduce the impingement of the drilling fluid while diverting the flow of the drilling fluid from an upstream annulus section of the system to the hollow central passage.

Abstract: Methods, systems, and devices for evaluating an earth formation. Methods may include conveying the carrier into a formation borehole; and using measure electrodes, in one mode of measurement, to make current measurements by applying a voltage to each measure electrode in a first set of sensor arrays while making first current measurements; and applying another high frequency voltage to each measure electrode in a second set of sensor arrays while making second current measurements. Optionally, methods include using the measure electrodes, in another mode of measurement, to make further resistivity measurements by applying a voltage to each measure electrode in both sets of sensor arrays while making third current measurements. Methods include combining first current measurements, second current measurements, and third current measurements to simulate a virtual impedance for each measure electrode. Optionally, any two consecutive sensor arrays around the circumference of the tool body are in different sets.

Abstract: A self-powered borehole communication assembly including a first electrode member having a first electrode potential and a second electrode member having a second electrode potential different than the first electrode potential. The first and second electrodes form an electrochemical cell when disposed in a borehole fluid that is at least partially electrolytic. The electrochemical cell is operatively arranged for producing a current and a voltage with at least one of the current or the voltage configured to directly convey information related to at least one borehole condition, property, or parameter. A method of communicating is also included.

Abstract: An apparatus for drilling a borehole into the earth includes a drill string configured to drill the borehole and a high-speed camera configured to capture a series of images of the drill tubular at a speed high enough to image information of interest while the drill tubular is in operation. The apparatus further includes a processor configured to receive and process the series of images to provide the information of interest.

Abstract: An underground directional drilling system can comprise a plurality of elongated dual-shaft segments coupled together end-to-end in a drilling string. The segments include an inner shaft that is independently rotable relative to an annular outer shaft, with the inner shafts being coupled together and the outer shafts being coupled together. The plurality of dual-shaft segments can comprise a communication segment that comprises a first electrode, a second electrode, a gap portion between the first and second electrodes that provides electrical insulation therebetween, and an electronic communication controller electrically coupled to the first and second electrodes. The communication controller is configured to generate voltage differences between the electrodes that cause electrical pulses to periodically transfer between the electrodes through the gap portion to wirelessly communicate drilling related data from underground to the surface.

Abstract: The invention is concerned with a tool and method for determining standoff from a formation though mud. The tool comprising a first electrode located at a distance from the formation for measuring a first impedance. A second electrode is located at a second distance from the formation for measuring a second impedance. A processing unit measures a difference between the first impedance and the second impedance, uses the difference to determine a conductivity of the mud and based thereon, determines the standoff of at least one of the first and the second electrode.

Abstract: Disclosed dielectric logging tools and methods employ three or more receive horn antennas positioned between at least two transmit antennas, which can also be horn antennas. The logging tools can operate in the range between 100 MHz and 10 GHz to provide logs of formation permittivity, formation conductivity, standoff distance, and electrical properties of material in the standoff gap. Logs of water-saturated porosity and/or oil movability can be readily derived. The presence of additional receive antennas offers a significantly extended operating range, additional depths of investigation, increased measurement accuracy, and further offers compensation for tool standoff and mudcake effects. In both wireline and logging while drilling embodiments, at least some disclosed dielectric logging tools employ a set of three axially-spaced receive antennas positioned between pairs of axially-spaced transmit antennas.

Abstract: An apparatus and method of performing a wellbore operation. The apparatus includes a drill bit that has a cavity at an end thereof and a communication device placed in the cavity. The communication device includes a first section and a second section. An outer dimension of the second section is greater than an outer dimension of the first section. The second section includes a conduit configured to allow passage of a conductor from the drill bit to a location outside the drill bit so as to provide a direct connection of the conductor from the drill bit to an element outside the drill bit.

Abstract: Disclosed is an adaptive borehole correction (ABC) technique based on an inversion approach that advantageously corrects shallow laterolog measurements for borehole effects, including determining and accounting for unknown tool eccentricity. The algorithm is based on simplex radial 1-D inversion where at every logging up to four unknowns are determined, namely tool eccentricity, Rt, Rxo, and Lxo. After that a borehole correction methodology is employed wherein the tool response in a borehole with real mud resistivity Rm is modified to a response in the borehole with virtual mud resistivity equal to Rxo.

Abstract: The present disclosure relates to determining a property, such as resistivity, of an earth formation. A transmitter is disposed in a wellbore penetrating the formation, and a plurality of receivers are distributed on or near the earth's surface. The transmitter sends electromagnetic energy into the formation and the resulting signal, after passing through the formation, is detected by the array of receivers. The received signal is used to determine the property of the formation. This is often achieved using an inversion or numerical model of the formation being measured. The inversion takes into account changes in the background formation model due to transmitting from various locations. The measurements made on the formation can be performed while drilling the wellbore or subsequent to the drilling.

Abstract: An apparatus for making a resistivity measurement of an underground formation surrounding a borehole is provided. The apparatus includes a conductive tool body, at least one current injector electrode positioned between the tool body and a wall of the bore hole, at least one current return electrode positioned between the tool body and the wall of the bore hole, an electrical measurement device configured to monitor a voltage or a current signal indicative of an impedance imbalance, a regulator connected to the electrical measurement device, whereby the regulator is configured to receive the voltage or the current signal indicative of the impedance imbalance and is configured to generate an adjustment signal based on the voltage or the current signal indicative of the impedance imbalance.

Abstract: In some embodiments, apparatus and systems, as well as methods, may operate to launch a set of currents into a corresponding set of existing well casings; monitor, in a well under construction, changes in at least one of a magnetic field or an electric field perturbed by the set of currents after each one of the set is launched; and determine a location of the well under construction in relation to the set of existing well casings. In some embodiments, the activities include inducing current into a drillstring located in a well under construction; monitoring, at a set of existing well casings, changes in at least one of a magnetic field or an electric field perturbed by the current after the current is induced; and determining a location of the well under construction in relation to the set of existing well casings. Additional apparatus, systems, and methods are disclosed.

Abstract: The present disclosure provides an apparatus and method for measuring electrical properties of an underground formation surrounding a borehole. The apparatus preferably comprises a downhole tool positionable in the borehole, a sensor pad positionable on the downhole tool, and a plurality of electrodes mounted on the sensor pad and configured to face a wall of the borehole. The apparatus further comprises an insulating layer extending over at least a portion of the plurality of electrodes facing the wall of the borehole.

Abstract: A drilling system includes integral drill bit body and logging while drilling tool body portions. There are no threads between the drill bit and the LWD tool. In one exemplary embodiment the drilling system includes a unitary tool body, i.e., a tool body formed from a single work piece. In another exemplary embodiment the drill bit body portion is welded to the LWD tool body portion. At least one LWD sensor is deployed in the drill bit. The drilling system enables multiple LWD sensors to be deployed in and near the bit (e.g., on both the side and bottom faces of the bit). The absence a threaded connection facilitates the placement of electrical connectors, LWD sensors, and electronic control circuitry at the bit.

Abstract: A timing detection device includes a draw back amount acquiring unit and a detecting unit. The draw back amount acquiring unit is configured to acquire a draw back amount of a received signal with respect to a peak value of the signal. The detecting unit is configured to detect the timing at which the draw back amount acquired by the draw back amount acquiring unit has exceeded a constant value as the timing at which a value of the signal is switched.

Abstract: A steerable, magnetic dipole antenna for Measurement-While-Drilling (MWD) or Logging-While-Drilling (LWD) applications. The antenna elements use a hole arrangement in addition to grooves in a steel tool body, which is typically a drill collar. This antenna embodiment is extremely robust, meaning that does not significantly reduce the structural integrity of the tool body in which it is disposed. The antenna embodiment is also relatively wear resistant. The resultant magnetic dipole generated by this antenna is also electrically steerable in inclination angle from a common origin. A variable dipole moment inclination angle combined with independently measured tool rotation orientation during normal drilling allows the antenna to generate a magnetic dipole moment that may be directed at any three dimensional angle and from a common origin point at the centroid of the antenna. The antenna can also be embodied to be more sensitive to resitivity in a particular azimuthal direction.

Abstract: The present disclosure relates to a method to determine a characteristic of a subsurface formation using a downhole logging tool. A downhole logging tool having the ability to make substantially concurrent disparate measurements on the subsurface formation is provided and substantially concurrent disparate measurements on the formation using the downhole logging tool are made. Those measurements are used to solve a system of equations simultaneously and the solution to the system of equations is used to determine the characteristic of the subsurface formation.

Abstract: A formation core analysis system can include an inner barrel and a toroidal electromagnetic antenna which transmits electromagnetic signals into a formation core when the core is received in the inner barrel. Another formation core analysis system can include an inner barrel and multiple longitudinally spaced apart electrodes which electrically contact a formation core when the core is received in the inner barrel. A speed of displacement of the core into the inner barrel may be indicated by differences between measurements taken via the electrodes as the core displaces into the inner barrel. A method of measuring resistivity of a formation core as the core is being cut can include transmitting electromagnetic signals into the core from a toroidal electromagnetic antenna as the core is being cut by a coring bit.

Abstract: An apparatus for making a resistivity measurement of an underground formation surrounding a borehole is provided. The apparatus includes a conductive tool body, at least one current injector electrode positioned between the tool body and a wall of the bore hole, at least one current return electrode positioned between the tool body and the wall of the bore hole, an electrical measurement device configured to monitor a voltage or a current signal indicative of an impedance imbalance, a regulator connected to the electrical measurement device, whereby the regulator is configured to receive the voltage or the current signal indicative of the impedance imbalance and is configured to generate an adjustment signal based on the voltage or the current signal indicative of the impedance imbalance.

Abstract: Methods for imaging geological structures include injecting magnetic materials into the geological structures, placing at least one magnetic probe in a proximity to the geological structures, generating a magnetic field in the geological structures and detecting a magnetic signal. The at least one magnetic probe may be on the surface of the geological structures or reside within the geological structures. The methods also include injecting magnetic materials into the geological structures, placing at least one magnetic detector in the geological structures and measuring a resonant frequency in the at least one magnetic detector. Methods for using magnetic materials in dipole-dipole, dipole-loop and loop-loop transmitter-receiver configurations for geological structure electromagnetic imaging techniques are also disclosed.

Abstract: An apparatus for measuring one or more earth formation properties during applications including formation evaluation and geosteering applications is provided. The apparatus includes: an elongated body; at least one recessed portion on a periphery of the elongated body; an electrically conductive coil forming a closed loop, at least a portion of the coil extending through the at least one recessed portion; and a u-shaped magnetically permeable and non-conductive material disposed between the coil and the at least one recessed portion, the u-shaped material partially surrounding the coil in the at least one recessed portion. A system for measuring one or more properties of an earth formation is also provided.

Abstract: In one aspect of the invention a downhole drill bit with a body intermediate a shank and a working surface. Extending from the work surface is a wear resistant electric transmitter electrically isolated from the drill bit body. A wear resistant electrically conductive receiver, also electrically isolated from the bit body, may be connected to a tool string component. The working surface may also have at least two wear resistant electrodes located intermediate the transmitter and receiver that are adapted to measure an electric potential in the formation.

Abstract: The invention is concerned with a tool and method for determining standoff from a formation though mud. The tool comprising a first electrode located at a distance from the formation for measuring a first impedance. A second electrode is located at a second distance from the formation for measuring a second impedance. A processing unit measures a difference between the first impedance and the second impedance, uses the difference to determine a conductivity of the mud and based thereon, determines the standoff of at least one of the first and the second electrode.

Abstract: An apparatus for detecting and avoiding an underground object during a horizontal directional drilling operation. The apparatus comprises a boring tool with a capacitive detection system. The boring tool is operatively connected to a drill string and advanced through the earth to create a borehole. The capacitive detection system includes a capacitive assembly and a processor. The capacitive assembly has first and second capacitive plates separated a known distance from an excitation plate. The capacitive plates detect a change in capacitance when the underground object is approached by the boring tool. The processor determines the distance to or location of the underground object from capacitance information sensed by the capacitive detection system. The distance and location information is transmitted to a machine operator.

Abstract: Method for removing air wave noise from shallow water controlled source electromagnetic survey data, using only the measured data and conductivity values for sea water (140) and air. The method is a calculation performed numerically on CSEM data and resulting in an estimate of those data that would have been acquired had the water layer extended infinitely upward from the seafloor. No properties of the sub-sea sediments are used. Synthetic electromagnetic field data are generated for (a) an all water model (141) and (b) an air-water model (146-147) of the survey region. These simulated results are then used to calculate (148-150) electromagnetic field values corresponding to a water-sediment model with water replacing the air half space, which represent measured data adjusted to remove air wave noise.

Abstract: An untuned, broadband receiver antenna for an induction or propagation logging tool reduces tool complexity, antenna coupling, and cross-talk between conductors to the antenna assemblies.

Abstract: Apparatus and probe for non-polarized contacts for resistivity measurements in drill cuttings. At least two probes having a highly conductive shell from non-corrosive metal in form of pipe and a wood and/or other fine channeled thread (grained) water filled that will be conductive when it is wet.

Abstract: Logging-while-drilling apparatus and methodologies for measuring streaming potential in an earth formation are provided. The apparatus and methodologies can be utilized to find information relevant to the drilling operations. In particular, since the streaming potential measurement relates directly to fluid flow, the streaming potential measurements can be used to track flow of fluids in the formation. In turn, this information may be used to find information relevant to the drilling operations, such as under-balanced drilling conditions, abnormal formation pressures, open fractures, the permeability of the formation, and formation pressure.

Abstract: A downhole tool for formation logging includes a tool body configured to move in a borehole; and at least one sensor module mounted in at least one mounting location on the tool body, wherein the at least one sensor module is interchangeable with other sensor modules that make different measurements. A downhole tool may further comprise a measurement system disposed in the tool body, wherein the measurement system is operatively coupled to the at least one sensor module.

Abstract: Resistivity measurements are made at a plurality of frequencies. An asymptotic high-frequency limit is determined and the electrical efficiency is estimated as a ratio of the high frequency resistivity limit to the low frequency resistivity. From the electrical efficiency, petrophysical parameters of a rock such as porosity and water saturation can be estimated. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Abstract: This disclosure, in one aspect, provides an apparatus for use in a wellbore that includes a member having an encoded magnetic field and a sensor proximate the encoded magnetic field that measures a change in the magnetic field due to a change in the load on the member. In another aspect, a method for measuring loads on a downhole tool is provided that comprises inducing an encoded magnetic field along a section of a member of the tool and detecting a change in the magnetic field due to a load on the member when the tool is in the wellbore.

Abstract: An azimuthally sensitive electromagnetic measurement tool is provided. The tool may be suitable, for example, to measure azimuthal variations of electrical properties of a subterranean formation. The tool includes a transmitter disposed to transmit electromagnetic energy into a subterranean formation and a longitudinally spaced receiver. At least one of the transmitter and the receiver includes a sector antenna. The sector antenna includes an exposed length of antenna wire that forms an arc about a portion of a circumference of the tool body. In one exemplary embodiment, the receiver includes first and second sector antennae, which, in combination, subtend a circular angle of about 360 degrees about the circumference of the tool body without substantially overlapping one another.

Abstract: A method and apparatus for obtaining a resistivity measurement of an earth formation surrounding a borehole in an MWD device uses the drillbit and the adjacent portion of the drill collar as a focusing electrode for focusing the measure current from a measure electrode on the face or side of the drillbit. This provides the ability to see ahead of and azimuthally around the drillbit.

Abstract: Sensor assemblies including transmitter and receiver antennas to respectively transmit or receive electromagnetic energy. The sensor assemblies are disposed in downhole tools adapted for subsurface disposal. The receiver is disposed at a distance less than six inches (15 cm) from the transmitter on the sensor body. The sensor transmitter or receiver includes an antenna with its axis tilted with respect to the axis of the downhole tool. A sensor includes a tri-axial system of antennas. Another sensor includes a cross-dipole antenna system.

Abstract: Earth formations are characterized by using an array of electrodes which can measure streaming potentials in the formation, and by interpreting the data obtained by the electrodes. The electrodes are placed on a wireline tool, a LWD tool, or in a fixed manner about a completed wellbore. The measured streaming potentials are generated by drilling with an overbearing pressure, slitting the mudcake in a borehole, acid injection, or any of various other manners which causes fluid movement. The data obtained is interpreted to locate fractures, measure formation permeability, estimate formation pressure, monitor drilling fluid loss, detect abnormal pressure, etc. Particularly, a streaming potential voltage transient having a double peak profile signifies the presence of a formation fracture.

Abstract: A repeater is disclosed in one embodiment of the present invention as including a cylindrical housing, characterized by a proximal end and a distal end, and having a substantially cylindrical wall, the cylindrical wall defining a central bore passing therethrough. The cylindrical housing is formed to define at least one recess in the cylindrical wall, into which a repeater is inserted. The cylindrical housing also includes an annular recess formed into at least one of the proximal end and the distal end. An annular transmission element, operably connected to the repeater, is located in the annular recess. In selected embodiments, the annular transmission element inductively converts electrical energy to magnetic energy. In other embodiments, the annular transmission element includes an electrical contact to transmit electrical energy directly to another contact.

Abstract: A logging-while-drilling tool is adapted for incorporation with a drill string having a longitudinal axis. The drill string is further adapted for drilling a wellbore penetrating a geological formation. The drilling tool includes a tool body having a central axis disposed in parallel relation with the longitudinal axis of the drill string and an external, circumferential surface spaced radially outward from the central axis. The tool also includes a measurement apparatus for measuring resistivity of a borehole fluid in the wellbore. The measurement apparatus has an electrode array including a current emitting electrode disposed on the circumferential surface. The current emitting electrode is adapted to emit current into a target region of the wellbore spaced laterally between the circumferential surface and the walls of the wellbore. Further, a current receiving electrode is disposed on the circumferential surface and spaced apart from the current emitting electrode.

Abstract: An MWD method and apparatus for determining parameters of interest in a formation has a sensor assembly mounted on a slidable sleeve slidably coupled to a longitudinal member, such as a section of drill pipe. When the sensor assembly is held in a non-rotating position, for instance for obtaining the measurements, the longitudinal member is free to rotate and continue drilling the borehole, wherein downhole measurements can be obtained with substantially no sensor movement or vibration. This is particularly useful in making NMR measurements due to their susceptibility to errors due caused by tool vibration. In addition, the substantially non-rotating arrangement of sensors makes it possible to efficiently carry out VSPs, reverse VSPs and looking ahead of the drill bit. A clamping device is used, for instance, to hold the sensor assembly is held in the non-rotating position.

Abstract: The invention provides an apparatus for making an electromagnetic measurement from within a subsurface borehole. The apparatus comprises an elongated support having electrically conductive segments and adapted for disposal within the borehole; an antenna adapted to transmit electromagnetic energy disposed on the support such that its axis is tilted or perpendicular with respect to the axis of the support; a sensor disposed on the support and adapted to detect a current flow along the support when the antenna is activated to transmit electromagnetic energy; and means to process the detected current flow to provide an indication of the measurement quality or the position of the support within the borehole.

Abstract: A interconnect structure is inexpensively manufactured and easily insertable into a socket. The interconnect structure is manufactured by forming a sacrificial substrate with cavities that is covered by a masking material having openings corresponding to the cavities. A first plating process is performed by depositing conductive material, followed by coupling wires within the openings and performing another plating process by depositing more conductive material. The interconnect structure is completed by first removing the masking material and sacrificial substrate. Ends of the wires are coupled opposite now-formed contact structures to a board. To complete the socket, a support device is coupled to the board to hold a tested integrated circuit.

Abstract: An apparatus for monitoring conditions in subterranean borehole during drilling and pullback operations in real time. The apparatus includes a drill string having a working end. A measurement system suitable for measuring at least one operational characteristic of the apparatus and having a metallic section in direct contact with the drill string is operably connected to the working end of the drill string. At least one toroid is circumferentially disposed around a first portion of the metallic section and has toroidal electrically conductive windings. A non-conductive material is disposed around the toroid whereby contact between the toroid and a subterranean environment during operation of the apparatus is precluded.

Abstract: A method of measuring resistivity values in relation to the azimuthal displacement of a measurement sensor displayed on a measurement-while-drilling device in a wellbore environment is disclosed. The present invention also provides an instantaneous reading of resistivity values. A resistivity sensor measures a volume having a circular cross-section, and whose center is the geometric center of the tool. Averaging removes measurement errors, such as those due to tool motion. Information on the formation resistivity is obtained as a function of the location of the center of the tool. A method of acoustic standoff determines offset of the drill tool and distances to walls. The operator gains knowledge of bedding layer formation and dip from azimuthal dependence of standoff and resistivity values.

Abstract: Methods and apparatus for detecting and monitoring the borehole effect in subsurface measurements. Toroidal sensor configurations address the undesired axial electric currents that travel along the borehole when antennas with tilted or transverse axes are used to make electromagnetic measurements. Embodiments use currents measured along the instrument to determine the quality of measured logs, the borehole size, and instrument position or orientation within the borehole.

Abstract: A method of cathodic current optimization measures drill stem resistances along a well hole being drilled, correlates the drill stem resistances to respective types of underground formations at corresponding positions along the well hole, predicts a respective position of at least one anodic area on a well casing to be installed and determines an amount of cathodic current to be applied thereto.

Abstract: An integrated, single collar measurement while-while-drilling tool is presented that comprises formation sensors, directional sensors, pressure sensors, a mud pulse telemetry device, and a turbine-generator power device configured in a single collar housing that is no longer than a standard drill collar. No electrical connections are made across drill collar tool joints. The tool provides high reliability and ease of transportation.

Abstract: Systems and associated methods for tracking and/or guiding an underground boring tool use one or more detectors to measure the intensity of an electromagnetic field which is transmitted from an underground boring tool. The measured intensities may then be used to determine the location of the boring tool. In a dead reckoning embodiment of the invention, one detector may be employed while, in a position determination embodiment, two or more detectors may be employed. In any embodiment, physically measurable parameters may be used in addition to measured magnetic intensities. A highly advantageous mapping tool instrument for use in the position determination embodiment and a cubic antenna for use in any magnetic field detector are employed herein.