A system comprising a ground drilling device with a control device, the system including an input device functionally coupled to the control device for entering at least one parameter for operating the ground drilling device. The at least one parameter may include a parameter that causes the ground drilling device to start drilling. The input device may be configured as a remote control with a feedback device, which outputs a variable that a user can perceive i) tactilely, ii) visually, and/or iii) auditorily, and that depends on a) the operation of the ground drilling device, b) the operating state of the ground drilling device, and/or c) the signal of a detection device.

Systems and methods include a computer-implemented method for determining normalized apparent power. Drilling acoustic signals corresponding to a time domain and generated during drilling of a well. A fast Fourier transformation (FFT) is performed using the drilling acoustic signals to generate FFT data. Normalized FFT data is generated using normalization parameters and a drill string rotation rate record of a drill string used to drill the well. The drill string rotation rate is received during drilling. Normalized apparent power is determined from data points of a predetermined top percentage of the normalized FFT data within a lithological significant frequency range. The normalized apparent power is a measure of the power of the drilling acoustic signals and it is a function of the amplitude and frequency of the normalized FFT data. The lithological significant frequency range is a frequency range within which the drill sounds are more closely related with lithology.

System and methods for geosteering inversion are provided. Downhole tool responses are predicted for different points along a planned path of a wellbore during a downhole operation, based on each of a plurality of inversion models. Measurements of the downhole tool's actual responses are obtained as the wellbore is drilled over the different points during a current stage of the operation. The inversion models are clustered based on a comparison between the actual and predicted tool responses and a randomly selected centroid for each cluster. The inversion models are re-clustered using an average inversion model determined for each cluster as the centroid for that cluster. At least one of the re-m clustered inversion models is used to perform inversion for one or more subsequent stages of the downhole operation along the planned wellbore path. The planned wellbore path is adjusted for the subsequent stage(s) of the downhole operation.

A system is described for calculating and outputting micro invisible lost time (MILT). The system may include a processor and a non-transitory computer-readable medium comprising instructions that are executable by the processor to cause the processor to perform various operations. Time-stamp data that includes values of drilling parameters may be received about a drilling operation, and the values of drilling parameters may be classified into a rig state that includes rig activities. For each rig activity, an actual completion time may be determined and compared to an expected completion time for determining a deviation. At least one deviated activity, in which the deviation is greater than a threshold, may be determined. Deviations may be combined into MILT that can be output for controlling the drilling operation.

In some examples, a method performed by a drilling rig control center, includes receiving raw data for a first time segment, the raw data related to a drilling operation. In addition, the method includes deriving first drilling state measurements based on the raw data of the first time segment. Further, the method includes deriving first formation state measurements based on the raw data of the first time segment. The method also includes correlating the first derived drilling and formation state measurements of the first time segment with a second derived drilling and formation state measurements of a second time segment. Still further, the method includes generating a control response based on the correlation.

Disclosed is a directional well trajectory control method based on drill pipe drive, the method including the following steps: parameters down-transmission, determining the offset vector, closed loop control of eccentric ring rotation angle, and well parameter closed-loop control; this method can achieve three-dimensional well trajectory control without frequent trips during drilling operations, and has a high penetration rate, good wellbore cleaning effect, well trajectory control accuracy, high flexibility, low tripping times, high borehole quality, high safety, etc., which is suitable for the development of special process wells such as medium-deep wells, ultra-deep wells, ultra-thin oil layer horizontal wells and unconventional oil and gas wells in China's complex oil and gas reservoirs. This method can also achieve precise control of well trajectory, and overcome the shortcomings of existing control methods that cannot achieve closed-loop control and cannot remove interference signals.

A first characteristic of a first discharge of electrodes of a pulse power drilling assembly in a borehole of a subterranean formation is determined. The first characteristic is based on a measurement of the first discharge. A second characteristic of a second discharge of the electrodes is determined. The second discharge occurs after the first discharge, and the second characteristic is based on a measurement of the second discharge. A difference between the first characteristic and the second characteristic is determined. A boundary layer of the subterranean formation is determined based on the difference.

A method for measuring the thickness of casing in a wellbore and/or analyzing the inner surface of the cased or non-cased wellbore. The method includes an positioning an untethered logging tool in a drill string, receiving the logging tool in a catcher positioned within the drill string, positioning a plurality ultrasonic transducers with the average distance between the outer surface of the plurality of transducers and an interior surface of the catcher sub being less than 0.8 mm, and moving the drill string and the logging tool toward a mouth of the borehole while transmitting acoustic waves through the catcher sub toward the wellbore casing and receiving acoustic waves back to the logging tool after the acoustic waves interact with the wellbore casing and reflect through the catcher.

In a method for determination of properties of cuttings from rock drilling the cuttings are crushed between at least two rollers, at least one roller being driven by a motor. A mechanic specific energy of the cuttings is determined by measuring the energy applied by the motor.

The disclosure presents processes and methods for determining an overpull force for a stuck drill string in a borehole system. The fluid composition of a mud in the borehole at a specified depth can be broken down into a percentage of liquid and percentage of solids, as well as adjusting for material sag and settling factors. The fluid composition can be utilized to identify friction factors and drag in respective fluid composition zones. Each friction factor and drag can be summed to determine a total fluid drag on the drill string. In some aspects, the total fluid drag can be adjusted utilizing the relative positioning of casing collars and tool joints. The total fluid drag can be summed with the other force factors, such as a shear force and mechanical drag. The total drag can then be utilized as the overpull force applied to the stuck drill string.