Schlumberger

A computerized method for evaluating a drill cuttings lithology includes acquiring a digital image of drill cuttings and segmenting the acquired image at a rig site to demarcate individual particles in image. Features are extracted from selected ones of the demarcated particles in the segmented image and the demarcated particles are further assigned to at least one group based on the extracted features at the rig site. A rig site user is prompted to input measurement data, a label, or a description of the at least one group. The segmented image, the extracted features, the assigned grouping, and the user input are electronically transferred to a cloud computing resource which performs a lithological classification of selected ones of the demarcated particles based on the extracted features and the user input and generates consolidated summary results of the lithological classification.

A system for a permanent magnet synchronous motor (PMSM) includes: a command controller dividing a torque command value by a motor torque constant to generate a reference quadrature component value (CV) of a stator current (I_{q_ref}), an offset controller: receiving and offsetting a fixed rotor angle value (θ_{e_fixed}) by -90° to output an applied rotor angle value (θ_{e_applied}), a torque controller: receiving a reference direct CV of the stator current (I_{d_ref}) combined with a direct CV of stator current (I_d), outputting a direct component of stator voltage (V_ds), receiving the I_{q_ref} combined with a quadrature CV of stator current (I_q), and outputting a quadrature component of stator voltage vector (V_qs), a transfer function generator: receiving the V_ds, V_qs, and θ_{e_applied}, and generating first and second voltage values, and a space vector PWM generator: receiving the first and the second voltage values and generating a PWM waveform for the PMSM.

Certain aspects of the present disclosure provide a method for removing PFAS contaminants from a PFAS contaminated aqueous stream. The method includes introducing the PFAS contaminated aqueous stream into a reactor with a photocatalyst reagent in the presence of UV radiation and ultrasonic energy to degrade the PFAS contaminants and produce a treated aqueous stream comprising byproducts of the degraded PFAS contaminants.

A spring shoulder kit (114) includes an expanding shoulder (130) and a retaining sleeve (132). The expanding shoulder (130) includes a wedge (146) outwardly radially extending from a radially flexible finger (140). The retaining sleeve (132) is slidably insertable into the expanding shoulder (130) to block inward radial movement of the wedge (146).

Methods and systems are provided for detecting and mitigating stall of a downhole motor driven by flow of drilling fluid through the downhole motor, which employ a BHA that includes at least one first downhole sensor and at least one second downhole sensor operably disposed above the downhole motor. The methods and systems generate time-series first data representing measurements of the rotational speed of a collar disposed at the uphole end of the downhole motor or part of the BHA disposed above the downhole motor made by the at least one first downhole sensor over time as well as time-series second data representing measurements of the vibration of the BHA made by the at least one second downhole sensor over time. Stall of the downhole motor can be automatically detected by analysis of the time-series first data and the time-series second data. Upon detecting stall of the downhole motor, at least one action can be initiated to mitigate the stall of the downhole motor.

A method for determining a recalibration trigger for a downhole survey sensor includes obtaining historical calibration and recalibration data for a plurality of downhole survey sensors. The historical calibration data is evaluated to determine calibration changes for selected ones of the survey sensors. A probabilistic model is constructed from the determined calibration changes over a predetermined range of temperatures and benchmarked against at least one industry standard to estimate the recalibration trigger.

Systems and methods for direct arrival estimation for marine seismic data are provided. A computer-implemented method for estimating direct-arrival energy in seismic data acquired in a marine environment, the method including: executing, by one or more processors, operations on seismic data that contain up-going and down-going wavefields in which direct-arrival information is not properly or completely recorded, processing the seismic data using a computer-based wavefield-analysis technique to identify water-layer reverberation events within the up-going and down-going wavefields, leveraging, through computer-implemented analysis, stable relationships among water-layer reverberations, computing, by the processors, an estimated direct-arrival signal based on the identified relationships to compensate for missing or improperly recorded direct-arrival information, and producing, using the processors, a direct-arrival estimate configured for use in subsequent seismic-processing operations.

A downhole tool for a drillstring that includes a mud motor (310) and a drill bit (304) can include sensor circuitry that acquires data characteristic of operation of the mud motor, wherein the mud motor is disposed on the drillstring between the downhole tool and the drill bit; and a telemetry interface for transmission of one or more of the data and data derived metrics.

A first velocity model having a three-dimensional (3D) grid of voxels containing velocity values is processed with an eikonal solver to generate a reference travel-time model as a second 3D grid of voxels containing respective reference travel-time values. A candidate background model is initialized based on the first velocity model. A candidate travel-time model is generated from the candidate background model. The candidate travel-time model has a third 3D grid of voxels containing respective candidate travel-time values. The candidate background model is updated to minimize a measure of difference between respective candidate travel-time values of the candidate travel-time model and respective reference travel-time values of the reference travel-time model. The updated candidate model serves as a second velocity model of the subsurface region that is kinematically equivalent to the first velocity model.

Methods and systems for drilling a wellbore that traverses a subterranean formation employ a computational model that relates input data representing at least one drilling performance parameter (or change therein) at one or more drilling conditions to output data representing at least one petrophysical formation property. Data representing at least one drilling performance parameter (or change therein) at one or more drilling conditions while drilling is determined by sweeping wellbore pressure over a range of pressures and measuring and analyzing wellbore pressures and associated drilling performance parameters, and such data is used as input data to the computational model, which generates output data representing at least one petrophysical formation property associated with the input data. The data output by the model can be added to well log of formation properties, which can be used to set or adjust the direction of drilling.