Abstract: Systems and methods of controlling drilling operations including Sliding With Indexing For Toolface (SWIFT) and Variable Weight Drilling (VWD) techniques. The methods and systems may include systems and devices for controlling the drilling operations, including systems and devices capable of automatically determining drilling parameters and setting operating parameters for drilling in a wellbore. The systems and methods may also determine a change in weight on bit, toolface, and/or differential pressure, determine a timeframe for a weight on bit to be delivered to the bit, and/or determine a spindle change to modify the toolface, and/or determine a change in differential pressure to be applied to modify toolface. The systems and methods may also send control signals to apply the spindle change and/or block velocity change and/or differential pressure change to correct any detected or anticipated toolface error.

Abstract: An apparatus for use in a wellbore includes a drill string section, a drive shaft disposed in the drill string section, a bearing assembly connected to the drive shaft, and an alignment assembly connecting the bearing assembly to the drill string section. The alignment assembly has a first alignment member and a second alignment member slidingly engaging one another to allow at least a portion of the bearing assembly to tilt relative to the drill string section. A related method includes the steps of positioning a drive shaft in a drill string section; connecting a bearing assembly to the drive shaft using the alignment assembly, the alignment assembly having a first alignment member and a second alignment member; and allowing at least a portion of the bearing assembly to tilt relative to the drill string section using the alignment assembly by having the first alignment member and the second alignment member slidingly engage one another.

Abstract: A drilling system configured to reduce friction during slide drilling. The drilling system has a drill string comprising a fluid-driven drill stage such as a mud motor; a variable frequency drive configured to oscillate the drill string via a quill and a sensor array. The sensor array measures the torque applied to the quill and the angular position of the quill. A controller is used to control the variable frequency drive based on the determined applied torque and quill angular position to meet predetermined oscillation turn-around criteria and to reduce the time to reduce the angular velocity of the quill from a maximum rotational speed to zero in an oscillation cycle.

Abstract: An activation control module utilizes gravity and/or centrifugal acceleration to move a mechanical element that controls, activates or deactivates a mechanical or hydraulic mechanism, for use with a downhole tool such as a drilling tool or reamer in a wellbore. In embodiments, the activation control module described herein may utilize a combination of centrifugal acceleration and/or gravity due to an inclination of the downhole tool to move a valve, which turns off pressure to a hydro-mechanical system. The activation control modules may be utilized in applications where very little space is available for larger mechanisms. Further, the activation control modules do not require expensive and complex electro-mechanical systems, reducing or eliminating the need for batteries, wiring, electronics, motors, pumps and the like. Moreover, the activation control modules described herein do not require the use of a turbine, a centrifugal clutch or a linear actuator.

Abstract: Methods and apparatus for including obtaining raw surface data for present values of torque (TTD) generated by a top drive operably coupled with a drillstring, obtaining raw surface data for present values of rotational speed (?) of the top drive corresponding to the TTD, obtaining inertia (JTD) of the top drive, and estimating torque TST of the drillstring based on the obtained TTD data, the obtained data, and the obtained JTD data. The estimated drillstring torque TST may be utilized to determine a surface torque oscillation performance index (STOPI).

Abstract: The disclosed embodiments include a rotating survey tool. The rotating survey tool includes a first sensor array that in operation collects a first set of survey measurements during a downhole drilling operation. Additionally, the rotating survey tool includes a second sensor array directly coupled to the first sensor array that in operation collects a second set of survey measurements while a drill bit drills during the downhole drilling operation. Further, the second set of survey measurements has a greater base accuracy than the first set of survey measurements.

Abstract: An antenna arrangement. The arrangement uses four conductive loops, each within a distinct plane from the other conductive loops. The four conductive loops have a common center point. Each loop is within a dipole magnetic field, and detects a component thereof. By balancing the signals received between matched pairs of the conductive loops, the difference between the signals can be used to guide the antenna arrangement to a null point—that is—a point in the magnetic field where each pair of conductive loops is balanced. The antenna arrangement can further be used to determine the depth of the dipole field source using the magnitude of the field.

Abstract: A push-pull force control method for a horizontal directional drilling machine with the following steps is provided. According to a correspondence relationship between a motor displacement and a maximum push-pull force of a drilling machine, the motor displacement is first adjusted, so that the required push-pull force can be obtained through the adjustment of the subsequent steps. Then, an oil feeding pressure of the motor is controlled according to a relationship between the push-pull force and the working pressure difference of the motor. Finally, the push-pull force of the motor is controlled in real time according to the oil feeding pressure of the motor to be equal to the required push-pull force value.

Abstract: A directional drilling system includes a rotary steerable tool. The rotary steerable tool includes an extendable member configured to extend outwardly from the rotary steerable tool upon actuation, and a geolocation electronics device configured to track a position of the rotary steerable tool and the extendable member and control actuation of the extendable member. The geolocation electronics device and extendable member are configured to rotate with the rotary steerable tool.

Abstract: Apparatus and operational methods thereof, including a top drive, a rotation sensor, and a processing device. The top drive connects with an upper end of a drill string. The rotation sensor facilitates rotational distance measurements indicative of rotational distance achieved by the top drive. The processing device causes the top drive to impart rotational oscillations alternatingly in opposing directions to the upper end of the drill string while maintaining a downhole toolface orientation during a slide drilling operation, such that each rotational oscillation rotates the upper end of the drill string through a base rotational distance. The processing device also causes the top drive to change the downhole toolface orientation by an offset rotational distance by adding the offset rotational distance and an overshoot rotational distance to the base rotational distance of an instance of the rotational oscillations.

Abstract: A steering head for steering a drill string may include a pad pusher including a steering pad and a piston. The steering pad may have a pivot axis, and be rotatable about the pivot axis between retracted and extended positions. The pad pusher may further include a motion restrictor to restrict rotation about the pivot axis. The steering head may further include a housing having a motion restrictor disposed at a position corresponding to the pad pusher motion restrictor. The pad pusher motion restrictor may be engageable with the housing motion restrictor to restrict motion of the steering pad relative to the housing.

Abstract: A drill string sub for a rotary steerable drilling system wherein a flow diverter is configured, which flow diverter is configured rotatable about a drill string longitudinal axis at a relative rotation frequency relative to the drill string sub, to preferentially direct drilling fluid into a selected azimuth segment which is stationary relative to the flow diverter. A downhole data unit is configured to provide an information signal representing downhole data. An encoder operatively connected to the flow diverter to modulate the relative rotation in accordance with the information signal for transmitting information representing the downhole data to be detected uphole.

Abstract: Systems and methods presented herein include a drilling system that includes a deflecting device having an internal passage extending therethrough, and a flexible drilling assembly configured to extend through the internal passage of the deflecting device, and to create a perforation lateral tunnel in a wellbore. The flexible drilling assembly includes a flexible drive shaft configured to rotate relative to the internal passage of the deflecting device. The flexible drilling assembly also includes a cutting bit disposed at a first axial end of the flexible drilling assembly. The flexible drilling assembly further includes a slider tube disposed at a second axial end of the flexible drilling assembly. In addition, the flexible drilling assembly includes a slider radially disposed within the slider tube.

Abstract: A planning tool plans movement of a boring tool for an underground drilling operation. The planning tool includes one or more wheels for rolling on a surface of the ground along a path responsive to movement by an operator to characterize the surface contour and to generate guidance for the boring tool to reach a target position. Planning can additionally be based on waypoints. The planning tool can be rolled unidirectionally or bidirectionally to characterize the surface contour. Bidirectional movement cancels accelerometer fixed bias. Path stitching is used to plan around obstacles. The planning tool can facilitate tracker placement. The planning tool can collect noise information for frequency selection purposes. A described technique maximizes linear drilling in an underground plan. Compensation and/or warnings are provided for unsteady, fast and slow movement of the planning tool while measuring the surface contour.

Abstract: A boring tool moves having a pitch orientation, a yaw orientation and a roll orientation and is steerable underground using the roll orientation. A maximum drill string curvature is established for steering. The boring tool is advanced over a path segment. An averaged roll characteristic is determined for movement of the boring tool along the path segment. A path segment pitch orientation is established based on at least one measured pitch orientation along the path segment. Using the maximum drill string curvature in combination with the averaged roll characteristic and the path segment pitch orientation, the yaw orientation is determined. The averaged roll characteristic is determined based on a series of incremental roll measurements that are spaced across the path segment. A set of coupled ordinary differential equations is used to characterize movement of the boring tool.

Abstract: A brake system for maintaining an angular position of a spindle assembly. A pump-powered motor drives rotation of a spindle on the machine. When no rotation is desired, the spindle will slow, then stop at a desired angular orientation. A rotational sensor will determine the clock position, and a controller compares that to a desired angular orientation. If an error tolerance is exceeded, the motor will rotate the spindle back to the desired orientation.

Abstract: A method device, and system is described herein for pushing a rotary drill bit. Pushing the rotary drill bit ears include receiving a target direction in a formation to push the rotary drill bit wile drilling a wellbore in a formation. Pushing the rotary drill bit can also include opening, at a first rotational position of a rotary bit pushing device disposed proximate to the rotary drill bit within the wellborn, a first inlet port of a first flow regulator. Pushing the rotary drill bit can further include closing, after the first rotational position of the rotary bit pushing device the first inlet port. Pushing the rotary drill bit can also include sending, to a second flow regulator of the rotary bit pushing device, a second quantity of drilling fluid.

Abstract: A method of monitoring a rock drilling and a rock drilling device includes generating a stress wave, which propagates in a tool of the rock drilling device, measuring the stress wave propagating in the tool and measuring a drilling parameter indicating a drilling penetration rate. The method further includes identifying, from the measured stress wave propagating in the tool, at least one of a compressive stress wave and a tensile stress wave of a reflected stress wave reflected from a rock to be drilled back to the tool, determining at least one property of the at least one of the compressive stress wave and the tensile stress wave of the reflected stress wave, detecting, on the basis of a change in the at least one property of the at least one of the compressive stress wave and the tensile stress wave, that the tool is approaching the cavity.

Abstract: A method for drilling a wellbore, wherein use is made of a top drive device including: multiple electric top drive motors each having a rotor, a transmission to which the rotors of the multiple top drive motors are operatively connected, a rotary stem or quill operatively connected to the transmission allowing the rotary stem or quill to be driven by the top drive motors in order to impart rotary torque to a drilling tubulars string connected to the rotary stem or quill of the top drive device, wherein at least one, preferably each, of the top drive motors has an operable clutch device configured to selectively connect and disconnect upon command the rotor relative to the transmission. The method includes providing a command to the one or more top drive motors having a clutch so as to selectively connect and disconnect the rotor thereof relative to the transmission by operating the clutch.

Abstract: An apparatus and method are used in conjunction with a system for performing horizontal directional drilling, the system including a drill string extending from a drill rig to a boring tool such that the boring tool is steerable based on a roll orientation. The system also includes an arrangement for generating steering commands for guiding the boring tool to a target position. Responsive at least in part to the steering commands, a display is configured to selectively indicate each of a rotate command, a push command and a spin command. A steering indicator is described which indicates a current roll orientation of the boring tool. A 3-D grid can be animated and centered on either a steering or target indicator. Rounding of a steering command ratio can limit the display of target roll orientations to only those that a given boring tool transmitter is capable of sensing and indicating.

Abstract: A calibration system for a surgical instrument. The calibration system includes an actuator, such as a motor system and a flexible shaft. The calibration system also includes a surgical instrument actuatable by the actuator. The calibration system also include calibration data corresponding to the surgical instrument. A processor is configured to process the calibration data for determining a position of the surgical instrument. The calibration system may include a sensor configured to provide a signal corresponding to a movement of the actuator, the processor being further configured to process the signal for determining a position of the surgical instrument.

Abstract: A method and a resistivity image logging tool connected or connectable to one or more processing devices process geological log data to construct missing information from destroyed or occluded parts using cues from observed data. The geological log data signals can be generated through use of the logging tool having one or more electrodes interacting with a formation intersected by a borehole. The processing involves the steps of: in respect of one or more data dimensions associated with missing values in a log data set, decomposing the signal into a plurality of morphological components; and morphologically reconstructing the signal such that missing values are estimated.

Abstract: A reel assembly for deploying a cable, hose or umbilical connection may include an electronic control unit that may operate to control the reel assembly. A sheave that redirects the direction of the cable, hose or umbilical connection may include sensors that may measure various parameters, such as a measured line tension and/or a length of cable, hose or umbilical connection that has been deployed, and transmit the measured data to the electronic control unit. The electronic control unit may, based on received sensor data, automatically direct the operation of the reel assembly. Optionally, the sensor data and/or user control inputs and system status information may be logged. The system also may use this data to control the system, such as by activating an alarm when a certain alarm limit is exceeded by the data, adjusting parameters of the drive, and the like.

Abstract: A system and method of automating a slide drilling operation comprising a plurality of tasks is described. The method includes presenting, on a GUI, selectable indicators, with each indicator being associated with one task from the plurality of tasks; wherein the GUI is coupled to a controller in communication with drilling equipment, wherein the controller is configured to: receive data from the drilling equipment; and control the drilling equipment using predetermined workflows and task parameters; receiving a selection command associated with: a selectable indicator, a first task, and a first predetermined workflow; presenting on the GUI, in response to the receipt of the selection command, a dialogue box for receiving task parameters associated with the first predetermined workflow; receiving, using the dialogue box, the task parameters; and executing, using the controller and the drilling equipment, the first task using the first predetermined workflow and the first plurality of task parameters.

Abstract: Systems and methods are provided for producing a continuous survey of a previously drilled portion of a wellbore. The method includes receiving a plurality of stationary survey measurements taken at a corresponding plurality of locations along the portion of the wellbore. The method further includes receiving at least one continuous survey including a plurality of continuous survey measurements taken between a pair of stationary survey measurements of the plurality of stationary survey measurements. The method further includes combining the plurality of stationary survey measurements and the plurality of continuous survey measurements to produce the continuous survey of the portion of the wellbore.

Abstract: Various embodiments disclosed relate to bearing assembly for drilling a subterranean formation and methods of using the same. In various embodiments, the present invention provides a method of drilling a subterranean formation. The method includes flowing a drilling fluid through a drill string disposed in the subterranean formation, with the drill string including a bottom hole assembly including a bearing assembly including a low flow bearing. The method includes flowing a first part of the drilling fluid into contact with the low flow bearing, while simultaneously flowing a second part of the drilling fluid through a bypass channel around the low flow bearing. The method also includes discharging the first and second part of the drilling fluid between the bottom hole assembly and the subterranean formation.

Abstract: The present disclosure relates to systems and methods for determining the retraction rate of a coring bit based on sensed environmental factors associated with coring operations. In certain embodiments, a downhole tool is positioned in a wellbore extending into a subterranean formation, coring operations are commenced by rotating a coring bit of the downhole tool and extending the rotating coring bit into a first location along a sidewall of the wellbore, a first environmental factor associated with the coring operations at the first location is sensed, and a rate of retraction of the coring bit at the first location is determined based on the first sensed environmental factor.

Abstract: A radar array comprising a panel, the panel comprising a top side and a bottom side; a plurality of high-frequency antennas coupled into a high-frequency array coupled to the panel; at least one low-frequency resistive vee dipole transmitting antenna; and at least one low-frequency resistive vee dipole receiving antenna, wherein the at least one low-frequency resistive vee dipole transmitting antenna and the at least one low-frequency resistive vee dipole receiving antenna are coupled into a low-frequency array.

Abstract: Some aspects of what is described here relate to seismic data analysis techniques. A seismic excitation is generated in a first directional wellbore section in a subterranean region. A seismic response associated with the seismic excitation is detected in a second directional wellbore section in the subterranean region. Seismic response data based on the seismic response are analyzed to identify geomechanical properties of subterranean rock in a fracture treatment target region in the subterranean region. In some cases, the geomechanical properties include pore pressure, stress, or mechanical properties.

Abstract: Apparatus, systems, and methods for controlling activities on a drilling rig are described. The methods include installing a control system operably coupled to the drilling rig and having a user interface, receiving operational guidelines from the user interface that include a plurality of control limits associated with operational parameters of the rig, monitoring current values of the operational parameters, and automatically applying the control limits to the operational parameters during operation of the rig.

Abstract: A technique facilitates a drilling operation by providing a drill bit having limited magnetic influence. The drill bit comprises a bit head formed with a non-magnetic bit head material. Cutting elements may be attached to the bit head to facilitate cutting of rock and other formation material during drilling of a borehole. The drill bit also comprises a bit body formed with a non-magnetic body material. The bit head and the bit body are joined to construct a non-magnetic drill bit which has no or limited magnetic influences on, for example, sensors located proximate the drill bit.

Abstract: A fiber optic sensor is disposed in the elastomer of the stator of the mud motor in order to sense elastomer strain while drilling. The frequencies of micro stalls and stick slips are measured from the fiber optic sensor data by classification using thresholds or by converting time-domain measurements from the fiber optic sensor data to frequencies. For example, the frequencies are produced by accumulating a histogram over an interval of time or by computing a Discrete Fourier Transform over an interval of time. A plurality of fiber optic sensors also can sense angular position of the rotor of the mud motor for correlation of the micro stalls and stick slips with the angular position. The measurements of the micro stalls and stick slips are used to select remedial action such as changes in drilling parameters.

Abstract: System and method for deploying multiple antennas in an array configuration with unobstructed electromagnetic access to a formation outside of a casing, sequencing the transmitted signal to control the direction of transmission into the formation, receiving the reflected signals, and locating the position of the reflection based on the scanned transmission signal orientation and the direction of the received signal. Such a deployment of an antenna array with unobstructed electromagnetic access to the formation outside of the casing, sequencing of the interrogation signal, and analysis of the received signal relative to the transmitted signal direction form the basis for reflection image rendering as the transmitted signal is scanned by a sequenced stimulus signal.

Abstract: A method of controlling drill bit trajectory in a subterranean formation includes receiving drilling parameters for operating a specific bottomhole assembly (BHA), constructing, with a computer processor, a directional drill-ahead simulator including a computer model of the BHA and the subterranean formation, calculating axial motion and lateral motion of a drill bit connected to a bottom end of the BHA using formation parameters and drilling parameters, predicting bit walk of the drill bit by accounting for and calculating contact forces and frictional forces between the BHA and a wall of a borehole in the subterranean formation using the computer model of the BHA, and determining an adjusted drill bit trajectory to account for the predicted bit walk. The method includes determining adjusted drilling parameters for operating the BHA to substantially follow the adjusted drill bit trajectory and operating the BHA according to the adjusted drilling parameters.

Abstract: A control system that mitigates stick-slip vibrations at higher harmonics than currently available is disclosed. A controller of a top drive is set to a torque control mode instead of a speed control mode. The controller receives torque measurements and compares to a target torque value. The controller accelerates or decelerates the top drive by a generated current adjustment command. A slow integration speed control loop, at least an order of magnitude slower in response than the torque control loop, receives a RPM set point. The slow integration speed control loop compares the RPM set point to an actual RPM measurement and generates a torque command. The torque command is sent to the torque control loop which results in an acceleration or deceleration of the top drive to maintain a desired torque amount. The speed of the top drive is bounded by a speed limit control loop.

Abstract: A technique facilitates drilling of wellbores with a steerable system having a plurality of pads which may be selectively actuated in a lateral direction to apply a side force. Application of the side force is used to steer a drill bit. A valve system is positioned to control delivery of actuating fluid under pressure to individual pads in a manner that enables steering of the drill bit. The valve system allows drilling along a desired curve by controlling the flow of actuating fluid under pressure to specific steering pads at specific angular positions. The valve system also allows drilling along a desired trajectory by preventing exposure of the pads to the pressurized actuating fluid.

Abstract: Mud pulse telemetry systems and methods may employ a downhole pulser to encode a digital telemetry data stream as pressure fluctuations in a fluid flow stream. An arrangement of spatially separated sensors acquire pressure-responsive measurements at multiple positions within the plumbing of a drill rig. A receiver collects and digitizes the measurements from the spatially separated sensors and subjects them to a principal components analysis (PCA) to determine those one or more basis vectors associated the telemetry signal. The PCA process may employ decomposition of a spatial correlation/covariance matrix or a temporal-spatial correlation/covariance tensor. The selected basis vector(s) are then used to obtain the telemetry signal for demodulation into the telemetry data stream.

Abstract: Rock strength is estimated during drilling using a rate of penetration model or a modified mechanical specific energy models. The rock strength estimate can be used in conducting further drilling, for example by a drilling system. Drilling parameters may be altered as a result of determining rock strength, for example to avoid undesirable trending fractures, such as extensive vertical fractures.

Abstract: A system and method to plan and represent well activities using bar charts, while also providing the option to select specific time periods in which to represent the data and/or to compare the data with other wells. Additionally, the system provides the ability to chart a well activity plan and to edit an existing plan.

Abstract: An apparatus and method automatically tally drill string rods for use with a drilling machine. The machine comprises a rack and a rotary drive configured for longitudinal displacement between first and second longitudinal positions. A sensor system is configured to monitor the machine to detect a clamping force applied to rotationally immobilize the drill string and to detect a break-out torque generated by the rotary drive, detect a first longitudinal position of the rotary drive whereat the break-out torque is generated, and detect a second longitudinal position of the rotary drive whereat a make-up torque is generated by the rotary drive. A controller is configured to prevent release of the clamping force until the make-up torque is detected, and automatically enable release of the clamping force after the make-up torque is detected and, concordantly, to update a drill rod tally only when the first and second longitudinal positions are different.

Abstract: The rotation angle around x axis, inclination angle and directional angle of a boring bit are obtained from the value measured with an accelerometer (22) and a three axis magnetic sensor integrally provided within the boring bit attached to the top of a rod array for boring. From these obtained values and the length corresponding to a rod, the amount of varied position according to boring by a length corresponding to a rod is obtained for each directional component. Further, the position of boring corresponding to boring in plural times with successive addition of rods is obtained through accumulating the amount of varied position for each directional component in respect of boring in plural times.

Abstract: A steerable earth boring assembly which includes an annular collar and a drive shaft with a drill bit, where the shaft pivots with respect to the collar. An upper portion of the shaft inserts into an orientation sleeve which resides in the collar. An axial bore is obliquely formed through the sleeve, and in which the upper portion inserts. Rotating the sleeve causes precession of the upper portion, thereby pivoting the drill bit obliquely to the collar. Selective rotation of the sleeve orients the drill bit into a designated orientation for forming a deviated wellbore. Included in the assembly is a flow tube with an end in sealing contact with the drive shaft.

Abstract: A steerable earth boring assembly which includes an annular collar and a drive shaft with a drill bit, where the shaft pivots with respect to the collar. An upstream portion of the shaft inserts into an orientation sleeve which resides in the collar. An axial bore is obliquely formed through the sleeve, and in which the upstream portion inserts. Rotating the sleeve causes precession of the upstream portion, thereby pivoting the drill bit obliquely to the collar. Selective rotation of the sleeve orients the drill bit into a designated orientation for forming a deviated wellbore. Included in the assembly is a flow tube with an end in sealing contact with the drive shaft.

Abstract: The present disclosure is directed to a drilling system including a drill string with two or more drill pipes (e.g., tubular), a drive system configured to rotate the drill string, and a neutral point sub disposed proximate a neutral point of the drill string, where the neutral point sub is configured to detect motion of the drill string.

Abstract: Disclosed is a method for extracting shale oil and gas by fracturing, and chemical retorting in oil shale in-situ horizontal well and a process for implementing the method. In the method and process, an inclined well is drilled from the ground to the upper part of an underground oil shale stratum, and a horizontal well is drilled in parallel to the oil shale stratum in the upper part of the oil shale stratum. Behind the horizontal well and the inclined well in the upper part, an inclined well leading to the lower part of the oil shale stratum is drilled, and a horizontal well is drilled in parallel to the lower part of the oil shale stratum. Highly pressurized media are injected into the horizontal well in the upper part of the oil shale stratum.

Abstract: Bottom-hole pressure operating envelops for underbalanced drilling take into account the lithologies of the formations being drilled through.

Abstract: The present disclosure is directed to systems and methods for rotating a drill string to mitigate stick-slip oscillations. An embodiment includes a method of rotating a drill string driven by a drive system using a control system. The method includes measuring torque values of the drive system with a torque sensor. The method also includes determining a frequency of stick-slip oscillations at the drive system based on the torque values using the control system. The method also includes determining an estimated instantaneous rotational speed of the drive system with the control system based on at least the frequency of stick-slip oscillations and a characteristic impedance of the drill string. The method also includes adjusting the estimated instantaneous rotational speed based on changes in the torque values to define an adjusted estimated instantaneous rotation speed with the control system.

Abstract: A method, apparatus, and program product facilitate the management of time domain data in a collaborative petro-technical application environment by associating time domain data in a shared project or repository with a data-specific SRD value. By doing so, when the time domain data is retrieved into a local project or client application for a particular user, the SRD for the time domain data and the SRD for the local project or client application may be used to facilitate conversion of the time domain data for use with the SRD for the local project or client application.

Abstract: A computer-implemented method for determining elastic properties for a heterogeneous anisotropic geological formation is described herein. The method includes grouping sonic velocity data from a borehole section (or borehole sections) into a number of clusters (e.g., one or more clusters). The sonic velocity data is grouped into clusters using petrophysical log data from the borehole section. The method also includes inverting the sonic velocity data for the clusters to determine elastic properties for each cluster. In some cases, the elastic properties for the clusters are combined to determine a relationship between the elastic properties and formation heterogeneity.

Abstract: The present disclosure is directed to systems and methods for rotating a drill string to overcome issues related to static friction during drilling. An embodiment includes a drive system configured to rotate the drill string through variable angular displacements and at variable rotation speeds based on control signals received by the drive system, and a control system configured transmit the control signals to the drive system, wherein the control system is configured to generate the control signals based on pipe characteristics within the drill string and friction values associated with the drill string to establish a rotation pattern of the drive system to approach a desired effective reach of surface torque generated by the drive system on the drill string.