The way in which a fiber optic cable is wrapped around a casing string in a wellbore can be modeled using information from downhole sensor devices. For example, a system can include a fiber optic cable located along a length of a wellbore. The system can also include sensor devices located near the fiber optic cable at various depths to transmit acoustic signals indicating depths and orientations of segments of the fiber optic cable. The system can build a model describing how the fiber optic cable is positioned around the casing string based on the acoustic signals transmitted from the sensor devices. The system can also determine a target position for a perforating gun to perform a perforation operation through the casing string that avoids damaging the fiber optic cable. The system can output the target position for the perforating gun to an electronic device to facilitate the perforation operation.

The way in which a fiber optic cable is wrapped around a casing string in a wellbore can be modeled using information from downhole sensor devices. For example, a system can include a fiber optic cable located along a length of a wellbore. The system can also include sensor devices located near the fiber optic cable at various depths to transmit acoustic signals indicating depths and orientations of segments of the fiber optic cable. The system can build a model describing how the fiber optic cable is positioned around the casing string based on the acoustic signals transmitted from the sensor devices. The system can also determine a target position for a perforating gun to perform a perforation operation through the casing string that avoids damaging the fiber optic cable. The system can output the target position for the perforating gun to an electronic device to facilitate the perforation operation.

A boring tool that is moved by a drill string to form an underground bore. A transmitter transmits a time varying dipole field as a homing field from the boring tool. A pitch sensor detects a pitch orientation of the boring tool. A homing receiver is positionable at a target location for detecting the homing field to produce a set of flux measurements. A processing arrangement uses the pitch orientation and flux measurements with a determined length of the drill string to determine a vertical homing command for use in controlling depth in directing the boring tool to the target location such that the vertical homing command is generated with a particular accuracy at a given range between the transmitter and the homing receiver and which would otherwise be generated with the particular accuracy for a standard range, different from the particular range. An associated system and method are described.

A boring tool that is moved by a drill string to form an underground bore. A transmitter transmits a time varying dipole field as a homing field from the boring tool. A pitch sensor detects a pitch orientation of the boring tool. A homing receiver is positionable at a target location for detecting the homing field to produce a set of flux measurements. A processing arrangement uses the pitch orientation and flux measurements with a determined length of the drill string to determine a vertical homing command for use in controlling depth in directing the boring tool to the target location such that the vertical homing command is generated with a particular accuracy at a given range between the transmitter and the homing receiver and which would otherwise be generated with the particular accuracy for a standard range, different from the particular range. An associated system and method are described.

A method for magnetic ranging includes switching an electromagnet deployed in a target wellbore between at least first and second states and acquiring a plurality of magnetic field measurements at a magnetic field sensor deployed on a drill string in a drilling wellbore while the electromagnet is switching. The magnetic field measurements may be sorted into at least first and second sets corresponding to the first and second states of the electromagnet. The first and second sets of magnetic field measurements are then processed to compute at least one of a distance and a direction from the drilling well to the target. The electromagnet may be automatically switched back and forth between the first and second states independently from the acquiring and sorting of the magnetic field measurements.

A system includes a drillstring with an electromagnetic (EM) transmitter in a first borehole. The system also includes at least one fiber optic sensor deployed in a second borehole. The system also includes a processor configured to determine a distance or direction of the EM transmitter relative to the at least one fiber optic sensor based on EM field measurements collected by the at least one fiber optic sensor in response to an EM field emitted by the EM transmitter.

An angular offset apparatus for determining an angular offset, or scribe line offset (SLO), of two objects within a drilling environment. The angular offset apparatus may include a sensing component and a target component located at various locations within the drilling environment. The sensing component may implement one or more sensors configured to collect data associated with the target component and the drilling environment to determine the SLO between the two objects. The angular offset apparatus, along with the calculated SLO, is designed to ensure accuracy and safety during drilling operations.

A system and method for monitoring a wellbore are disclosed herein. A pulse generator comprises a plurality of ports, wherein a first one of the plurality of ports is coupled to a first location of interest and a second one of the plurality of ports is coupled to a second location of interest. An electromagnetic pulse is generated at the first port and the second port. A reflected electromagnetic pulse is received at the first port and the second port. In another embodiment, the pulses are received at a separate pulse receiver with a plurality of receiving ports. A data storage device is coupled to the pulse generator or the pulse receiver, and data relating to the reflected magnetic pulse is stored at the data storage device.

A steering tool is movable by a drill string to form an underground bore along an intended path. A sensing arrangement of the steering tool detects its pitch and yaw orientations at a series of spaced apart positions along the bore, each position is characterized by a measured extension of the drill string. The steering tool further includes a receiver. At least one marker is positioned proximate to the intended path, for transmitting a rotating dipole field to expose a portion of the intended path to the field for reception by the receiver. The detected pitch orientation, the detected yaw orientation and the measured extension of the drill string are used in conjunction with magnetic information from the receiver to locate the steering tool. The steering tool may automatically use the magnetic information when it is available. A customized overall position determination accuracy can be provided along the intended path.

A method for locating a buried casing stub may comprise a) identifying a target region, b) providing at each of a plurality of survey points in the target region a casing stub locator that includes a vector magnetometer, c) measuring the magnetic field at each of the survey points using the vector magnetometer so as to generate a plurality of magnetic field measurements, d) using the magnetic field measurements to generate a model of the magnetic field of the target region, e) fitting the model generated in step d) to a selected model of a magnetic anomaly created by the casing stub so as to generate model fit information (MFI), and f) locating the casing stub using the MFI. At each survey point, an expected Earth magnetic field can be subtracted from the measured magnetic field. A total station can measure the position and/or the azimuth of the package.