A method includes deploying a logging tool in a borehole formed in a subsurface formation. The logging tool has a transmitter and a receiver. The method includes emitting, by the transmitter, a signal into subsurface formation. The method includes detecting, by the receiver, a response to the signal being propagated through the subsurface formation. The method includes creating, from the response, a borehole image that includes distorted features representing bedding dips in the subsurface formation. The method includes correcting the distorted features, wherein correcting the distorted features comprises mapping points of a non-circular shape in the borehole image to points on a circular shape.

A method includes deploying a logging tool in a borehole formed in a subsurface formation. The logging tool has a transmitter and a receiver. The method includes emitting, by the transmitter, a signal into subsurface formation. The method includes detecting, by the receiver, a response to the signal being propagated through the subsurface formation. The method includes creating, from the response, a borehole image that includes distorted features representing bedding dips in the subsurface formation. The method includes correcting the distorted features, wherein correcting the distorted features comprises mapping points of a non-circular shape in the borehole image to points on a circular shape.

System and method for determining the location of a bottom hole assembly (BHA) during drilling of a well are provided. During drilling, a computer system determines an increase in measured depth during a time interval, and adjusts the determined measured depth to account for tensile and compressive forces, which may stretch or compress, respectively, the length of the drillstring. The computer system also determines a curvature projection of the drillstring responsive to a plane of arc and a build rate estimate, and uses the curvature projection to determine a position of the BHA.

Disclosed herein is a device and method for correlating core sample zones with an actual subterranean depth. The disclosed device has a pair of independent distance measuring devices operably in communication with a core sample apparatus where a first distance measuring device measures the length of a core sample entering a core sampling tube and a second distance measuring device measures a drive depth of the core sampling tube entering into the ground. A processing unit is provided for correlating the two distances so as to allow a determination as to the actual depth below ground from where a given zone of the core sample is extracted.

A method of geosteering in a wellbore construction process uses an earth model that defines boundaries between formation layers and petrophysical properties of the formation layers in a subterranean formation. Sensor measurements related to the wellbore construction process are inputted to the earth model. An estimate is obtained for a relative geometrical and geological placement of the well path with respect to a geological objective using a trained greedy Monte Carlo agent. An output action based on the sensor measurement for influencing a future profile of the well path with respect to the estimate.

A method of geosteering in a wellbore construction process uses an earth model that defines boundaries between formation layers and petrophysical properties of the formation layers in a subterranean formation. Sensor measurements related to the wellbore construction process are inputted to the earth model. An estimate is obtained for a relative geometrical and geological placement of the well path with respect to a geological objective using a trained greedy Monte Carlo agent. An output action based on the sensor measurement for influencing a future profile of the well path with respect to the estimate.

A method (60) of determining core orientation of a core sample (12) cut from the ground by a drill rig (10) having a drill string and a drill bit (20) coupled to a downhole end of the drill string. Drilling data (Cn, Rn) is continuously acquired while the drill rig (10) is operating to cut and retrieve the core sample (12). The drilling data is a combination of core orientation data Cn and rig operational data Rn, where the rig operational data is constituted by either one or both of: (a) near bit rig data Nn; and, (b) at surface rig data Sn. The drilling data is analysed for a specific pattern of rig operational data Rn indicative of the core sample being broken from ground by operation of the drill rig (10). On detection of the specific pattern, the orientation of the core sample prior to being broken from the ground is the acquired core orientation data Cn coinciding with that specific pattern of rig operational data Rn.

Systems and methods for avoiding discrete 3D geological bodies that are hazards to drilling operations by identifying each 3D geological body near a well-path, defining the extents of each 3D geological body relative to the well-path, and displaying the extents of each 3D geological body relative to the well-path.

Disclosed herein is a device and method for correlating core sample zones with an actual subterranean depth. The disclosed device has a pair of independent distance measuring devices operably in communication with a core sample apparatus where a first distance measuring device measures the length of a core sample entering a core sampling tube and a second distance measuring device measures a drive depth of the core sampling tube entering into the ground. A processing unit is provided for correlating the two distances so as to allow a determination as to the actual depth below ground from where a given zone of the core sample is extracted.

Raw signal measurements can be received by sensors in a wellbore. Borehole effects can affect the raw signal measurements. The raw signal measurements can be converted into ratio signals having attenuation and phase shift. An apparent resistivity can be determined from the ratio signals. Mud resistivity can be determined based on apparent resistivity, at least part of the raw signal measurements, and the borehole size. A true resistivity can be determined based on the mud resistivity and at least part of the ratio signals. The raw signal measurements and the ratio signals can be updated based on the true resistivity. Steps can be repeated to determine a corrected true resistivity. Based on the true resistivity value and updated raw signal measurements and ratio signals, an operating characteristic of a well tool can be caused to be adjusted.