Abstract: A drilling system comprises a drillstring including a dill bit, a bottomhole assembly coupled to the drill bit, and a plurality of interconnected tubular members coupled to the bottomhole assembly. A first tubular member includes a communication link having a first annular inductive coupler element disposed in an annular recess in a first end, a second annular inductive coupler element disposed in an annular recess in a second end, and a cable coupling the first annular inductive coupler element to the second annular inductive coupler element. In addition, the drilling system comprises a first signal level determination unit disposed in the drillstring and configured to determine a level of a first signal communicated from the second inductive coupler element. Further, the drilling system comprises an axial load determination unit configured to determine an axial load at the first signal level determination unit based on the level of the first signal.

Abstract: A method for detecting hydrocarbon zones in a geological formation, including obtaining a plurality of pulverized drill cutting samples representative of the geological material encountered at measured depth intervals, each drill cutting obtained at periodic intervals during the drilling process; measuring each cutting sample with a color measuring device to obtain a value representing the degree of lightness of the particular cutting sample; and analyzing the measured lightness values by order of borehole depth that the respective cutting sample was obtained to determine the presence of geological zones likely to possess producible hydrocarbons. L* data may be combined with other well logging data to improve the hydrocarbon layer determination accuracy. A method also for locating the drill bit within a desired hydrocarbon layer during directional drilling.

Abstract: Methods comprising lowering a downhole tool via a pipe into a wellbore drilled through a formation via the pipe, establishing fluid communication between the downhole tool and the formation at a location in the wellbore, extracting from the formation a first fluid stream and passing the first fluid stream through the downhole tool for a first duration, breaking fluid communication between the downhole tool and the formation, reestablishing fluid communication between the downhole tool and the formation essentially at the location in the wellbore, extracting from the formation a second fluid stream and passing the second fluid stream through the downhole tool for a second duration, and capturing in the downhole tool a fluid sample of the second fluid stream.mud.

Abstract: An apparatus for cutting a wellbore includes a motor having a stator and a rotor. The rotor has an output shaft connected to a cutting structure. The stator and rotor are spaced radially outwardly of the axis of rotation of the rotor such that at least one of the stator and the rotor had an access bore extending through the motor to adjacent the cutting structure. A further object can pass therethrough, without obstruction. The further object comprises a further cutting. A flow diverter is disposed in the motor proximate a connection between the motor and a wellbore tubular, and has a first fluid outlet in fluid communication with a power section of the motor, and a second fluid outlet in fluid communication with the access bore. The flow diverter is coupled to the stator such that axial loading created by fluid pressure is substantially transferred to the stator.

Abstract: In accordance with aspects of the present disclosure, techniques for predicting, classifying, preventing, and remedying drilling fluid circulation loss events are disclosed. Tools for gathering relevant data are disclosed, and techniques for interpreting the resultant data as giving rise to an actual or potential drilling fluid lost circulation event are also disclosed.

Abstract: A method and apparatus for identifying a ballooning zone in downhole formations. In one embodiment, a method for identifying a ballooning zone in downhole formations includes disposing a drill string in a wellbore. The drill string includes a plurality of wired drill pipes connected end-to-end, and a bottomhole assembly connected to the drill pipes. While circulating drilling fluid through the wellbore, a first resistivity of a formation drilled is measured. While not circulating drilling fluid through the wellbore, a second resistivity of the formation drilled is measured. The first resistivity and the second resistivity are compared. Based on a result of the comparing, a level of ballooning attributable to the formations is identified.

Abstract: A microresistivity logging tool includes a monopole current injection electrode and at least first and second pairs of potential electrodes. The tool may further include a controller configured for making microresistivity anisotropy measurements using a single firing of the monopole current injection electrode. The controller may be configured to compute a two-dimensional tensor of the local formation resistivity from a single firing of the monopole current injection electrode. The use of a single firing tends to decrease measurement time, which in turn tends to improved azimuthal sensitivity in microresistivity anisotropy imaging while drilling applications.

Abstract: Apparatus and methods for monitoring and processing wellbore data are disclosed. An integrated digital ecosystem comprises an applied fluid optimization specialist and one or more sensors communicatively coupled to the applied fluid optimization specialist. The applied fluid optimization specialist receives data relating to performance of subterranean operations from the one or more sensors and interprets the data received. The applied fluid optimization specialist then regulates the performance of subterranean operations based on the interpretation of the data received.

Abstract: A method of drilling a wellbore can include drilling the wellbore with a continuous tubing drill string, and sensing at least one parameter with an optical waveguide in the drill string. A well system can include a continuous tubing drill string, and an optical waveguide in the drill string. The optical waveguide may sense at least one parameter distributed along the drill string.

Abstract: A drill bit made according to one embodiment may include a bit body having a longitudinal axis, a plurality of gamma sensors placed in the bit body, at least two gamma ray sensors in the plurality of sensors are spaced-apart from each other along the longitudinal axis of the bit body, wherein each such sensor in the plurality of sensors is configured to detect gamma rays from the formation during drilling of the wellbore and to provide signals representative of the detected gamma rays, and a circuit configured to process at least partially the signals from each of the at least two gamma ray sensors for estimating an inclination of the bit body relative to the longitudinal axis.

Abstract: An apparatus for measuring a characteristic of an earth formation includes a drill collar configured to be inserted into a borehole of the earth formation, an electromagnetic sensor on the drill collar, and a non-conductive sleeve surrounding a circumference of the drill collar including the electromagnetic sensor and configured to press directly against the electromagnetic sensor.

Abstract: Estimating formation parameters. At least some of the illustrative embodiments are methods including: combining a first plurality of actual logs from a first plurality of actual boreholes, at least one actual log associated with each actual borehole, and thereby creating a first equivalent log along a first equivalent path; combining a second plurality of actual logs from a second plurality of actual boreholes, at least one actual log of the second plurality of actual logs associated with each actual borehole of the second plurality of actual boreholes, and thereby creating a second equivalent log along a second equivalent path; and estimating a plurality of values of a parameter of one or more formations along a proposed borehole path, each value associated with a distinct depth along the proposed borehole path, the estimating using the equivalent logs.

Abstract: A probe for establishing fluid communication between a downhole tool and a subterranean formation is provided. The downhole tool is positioned in a wellbore penetrating the subterranean formation. The probe includes a platform operatively connected to the downhole tool, at least one packer operatively connected to the platform, the packer having at least one hole extending therethrough and at least one embedded member disposed in the packer for enhancing the operation of the packer as it is pressed against the wellbore wall.

Abstract: Drilling laterals in shale formations. At least some of the illustrative embodiments are methods including: drilling a deviated borehole through a shale formation with a drill string comprising a drill bit; logging the shale formation with a logging tool disposed within the drill string; estimating, in real time with the drilling, fracture potential of a portion of the shale formation near the drill bit, the estimation of fracture potential based on information acquired by the logging tool; and controlling drilling direction based on the fracture potential.

Abstract: The present invention relates to a process and related apparatus for determining the presence and/or quantity of H2S in the drilling debris of a subsoil layer comprising the following working steps: recovering the drilling debris of a layer; degassing the drilling debris from the previous recovery step, and separating a gaseous phase from said debris; clearing the gas released in the step of degassing, and conveying towards an H2S detector; determining the possible presence and/or quantity of H2S in the gaseous phase from the steps of degassing and clearing by means of a suitable means of detection; possible repetition of the previous phases at two layers, at least of the subsoil at different levels of depth in relation to the surface, with consequent determination of a distribution profile of H2S in the subsoil.

Abstract: A method of testing a core sample is provided. The method comprises determining an impedance map, attaching a sleeve to the core sample, and measuring a flow performance of the core sample. An impedance of each of a plurality of portions of the sleeve is based on the impedance map.

Abstract: Apparatus and methods for measuring properties of formation material and fluid in a borehole wall. In some embodiments, the apparatus includes a cylinder with a drawdown piston slideably disposed therein, a probe assembly and a passageway configured to provide fluid communication between the probe assembly and the cylinder. The probe assembly has a housing, a piston slideably disposed within the housing, the piston having a throughbore and a pad coupled thereto, and a tubular slideably disposed within the throughbore. The drawdown piston is translatable from a first position toward a second position to draw fluid into the probe assembly, the passageway and the cylinder, and translatable from the second position toward the first position to increase pressure of fluid in the passageway.

Abstract: Methods, computer programs, and systems for detecting at least one downhole condition are disclosed. Pressures are measured at a plurality of locations along the drillstring. The drillstring includes a drillpipe. At least one of the pressures is measured along the drillpipe. At least one downhole condition is detected based, at least in part, on at least one measured pressure.

Abstract: An apparatus for wireless communications in a drilling operations environment can include an instrument hub that is inline with drill pipe of a drill string. The instrument hub includes a sensor to receive downhole communications from downhole. The instrument hub also includes a transmitter to wireless transmit data representative of the downhole communications to a data processor unit.

Abstract: A method of servicing a wellbore comprises determining a cation exchange capacity of a sample of a shale, determining a swelling characteristic of the shale using the cation exchange capacity in an equation comprising a term of the form: Az% salt=x(cation exchange capacity)y where Az% salt is a final swelling volume of the shale in the presence of an aqueous fluid having a salt concentration of z %, and x and y are empirical constants, determining a composition of a wellbore servicing fluid based on the determined swelling characteristic, and drilling the wellbore using the wellbore servicing fluid.

Abstract: A method of measuring a formation parameter in the process of drilling a well penetrating the rock formation is disclosed. A section of the well is provided with a drill string comprising a drilling bit at its distal end; a first fluid is circulated through the drilling bit and invades the rock formation; a formation evaluation tool mounted onto the drill string is used to measure the formation parameter; the formation parameter is used to select the time at which a second fluid is circulated through the drilling bit; such that the second fluid alters the response of the rock formation to the formation evaluation tool; the second fluid is circulated through the drilling bit to start invading the formation; and the formation evaluation tool is used to repeat the measure of the formation parameter while circulating the second fluid.

Abstract: The present disclosure relates to a method to determine the capture cross-section of a subsurface formation at a desired depth in the formation. A database of Sigma values for known lithologies, porosities, and salinities is provided, and multiple Sigma measurements are obtained from a downhole logging tool. Within the database, Sigma values are interpolated to determine the respective depths of investigation of the multiple Sigma measurements. A monotonic function is fitted to the multiple Sigma measurements at the determined depths of investigation, and the capture cross-section of the subsurface formation at any desired depth in the formation is determined using the fitted function. Similarly, a system to determine the capture cross-section of a subsurface formation at a desired depth in the formation and/or a depth of invasion of drilling fluids is also disclosed.

Abstract: A system for synchronizing instruments in a drill pipe to detect formation characteristics comprises at least one first transmitter for transmitting a first signal, at least one first receiver for receiving a second signal having information based on the first signal, at least one acoustic transmitter for transmitting an acoustic signal, and at least one acoustic sensor electrically connected to one of the at least one first transmitter and the at least one first receiver, the at least one acoustic sensor for sensing the acoustic signal for synchronizing the at least one first transmitter and the at least one first receiver.

Abstract: Embodiments disclosed herein relate to one or more embodiments and methods to make downhole measurements. Embodiments disclosed herein relate to one or more embodiments and methods to measure the movement generated by a coring tool. The methods and embodiments include disposing a coring tool in a wellbore, coupling a first wave detector to the coring tool, anchoring the coring tool to a formation surrounding the wellbore, operating the coring tool, measuring movement generated by the coring tool with the first wave detector, and outputting a signal based upon the measured movement measured with the first wave detector.

Abstract: A microresistivity logging tool includes a monopole current injection electrode and first and second potential electrodes deployed on a downhole tool body. A controller is configured to apply a high frequency alternating current between the monopole current injection electrode and a return and measure a corresponding AC potential difference between the first and second electrodes.

Abstract: A method of signal processing includes providing at least a first pressure sensor and a second pressure sensor spaced in a drilling system and using an algorithm to separate the downwardly propagating waves from the upwardly propagating waves. In one or more examples, an algorithm may include determining a velocity of pressure signals in a wellbore, time-shifting and stacking pressure signals from at least the first pressure sensor and the second pressure sensor to determine a downwardly propagating noise signal, and subtracting the downwardly propagating noise signal from at least the signal from the first pressure sensor.

Abstract: A method for operating a pulsed neutron generator including an ionizer with an electron emitting cathode and a grid wherein the cathode and grid are disposed in a sealed chamber. At least one of the following is applicable to the ionizer; a distance between the cathode and the grid, a cathode current and/or a potential on the grid are selected such that the ionizer operates at most about one-half the space charge limited current for a grid current selected to provide a predetermined amount of neutron production.

Abstract: An assembly for drilling and logging includes a device for electro pulse drilling (EPD device), at least one device to receive acoustic signals generated by the EPD device, distinguished in that the assembly further includes at least one device to receive electromagnetic signals generated by the EPD device. A method for drilling and logging, and device for electro pulse drilling.

Abstract: A method of drilling a wellbore can include drilling the wellbore with a continuous tubing drill string, and sensing at least one parameter with an optical waveguide in the drill string. A well system can include a continuous tubing drill string, and an optical waveguide in the drill string. The optical waveguide may sense at least one parameter distributed along the drill string.

Abstract: The present invention relates to a control of a compressor (8) at a rock drilling apparatus, said rock drilling apparatus including a power source for driving a compressor (8) at a rock drilling process, said compressor (8) being arranged to operate according to a first mode and according to a second mode, wherein, in said first mode, the work produced by the compressor (8) is arranged to be controlled by controlling the rotation speed of said compressor (8), and wherein, in said second mode, the work produced by the compressor (8) is arranged to be controlled by controlling the air flow at the compressor inlet.

Abstract: An apparatus and method for reducing temperature along a bottomhole assembly during a drilling operation is provided. In one aspect the bottomhole temperature may be reduced by drilling a borehole using a drill string having a bottomhole assembly at an end thereof, circulating a fluid through the drill string and an annulus between the drill string and the borehole, diverting a selected portion of the fluid from the drill string into the annulus at a selected location above the drill bit to reduce pressure drop across at least a portion of the bottomhole assembly to reduce temperature of the bottomhole assembly during the drilling operation.

Abstract: A method of drilling a wellbore can include drilling the wellbore with a continuous tubing drill string, and sensing at least one parameter with an optical waveguide in the drill string. A well system can include a continuous tubing drill string, and an optical waveguide in the drill string. The optical waveguide may sense at least one parameter distributed along the drill string.

Abstract: An apparatus and method are provided for obtaining formation data while drilling. The apparatus may include a drill string and a plurality of sensors. At least two of the plurality of sensors are spaced apart along the drill string a approximately the same distance as a length of a segment of the drill string. The segment of the drill string is either added to or removed from the rest of the drill string as the drill string moves in the borehole during a drilling operation. The method may include providing numerous sensors along a drill string and repeating a cycle of various functions. The cycle may include performing an operation moving the drill string relative to the borehole and stopping movement of the drill string. Additional functions may include changing an overall length of the drill string and performing the formation property while the drill string is relatively stationary.

Abstract: A system and method for determining at least one fluid characteristic of a downhole fluid sample using a downhole tool are provided. In one example, the method includes performing a calibration process that correlates optical and density sensor measurements of a fluid sample in a downhole tool at a plurality of pressures. The calibration process is performed while the fluid sample is not being agitated. At least one unknown value of a density calculation is determined based on the correlated optical sensor measurements and density sensor measurements. A second optical sensor measurement of the fluid sample is obtained while the fluid sample is being agitated. A density of the fluid sample is calculated based on the second optical sensor measurement and the at least one unknown value.

Abstract: Job monitoring methods and apparatus for logging-while-drilling equipment are disclosed. A disclosed example method includes obtaining a fluid associated with an underground geological formation, analyzing the fluid with one or more sensors to form respective ones of sensor outputs, identifying a downhole scenario associated with the fluid based on the sensor outputs, the identifying being performed while the sensors are within the underground geological formation, and selecting a telemetry frame type based on the identified downhole scenario.

Abstract: The disclosure is directed to methods and apparatuses for estimating a response relating to a formation by stressing a wall of a borehole during either wireline or while drilling deployment. The response may be estimated by stressing the wall of a borehole formed in the formation; and estimating a response of the borehole wall to the stress. The response may be estimated using a force module configured to induce the stress around borehole and a tool configured to estimate the response of the borehole wall to the stress.

Abstract: A downhole tool for subsurface disposal is provided. The tool comprises an elongated tool body, an enclosure attached to an exterior surface of the tool body. The enclosure comprises at least one transducer disposed at an angle with respect to a longitudinal axis of the enclosure, and an electronics board coupled to and disposed adjacent to the at least one transducer. The enclosure also defines an internal cavity, and the internal cavity contains a fluid for insulating the at least one transducer from a downhole environment. The fluid is in direct contact with the at least one transducer and the electronics board.

Abstract: Apparatus, computer readable medium, and program code for identifying rock properties in real-time during drilling, are provided. An example of an embodiment of such an apparatus includes a downhole sensor subassembly connected between a drill bit and a drill string, acoustic sensors operably coupled to a downhole processor, a borehole telemetry system, downhole and surface data transmitting interfaces, and a surface computer operably coupled to the downhole data transmitting interface. The downhole processor is adapted to perform operations including receiving raw acoustic sensor data resulting from rotational contact of the drill bit with rock, transforming the raw acoustic sensor data into the frequency domain, filtering the transformed data, and deriving acoustic characteristics from the filtered data. The surface computer is adapted to perform operations including deriving petrophysical properties from the acoustic characteristics directly or by utilizing a petrophysical properties evaluation algorithm.

Abstract: Methods of identifying rock properties in real-time during drilling, are provided. An example of such a method includes connecting a downhole sensor subassembly between a drill bit and a drill string, operably coupling acoustic sensors to a downhole data interface, and operably coupling a surface computer to the downhole data interface. The method can also include receiving raw acoustic sensor data generated real-time as a result of rotational contact of the drill bit with rock during drilling, transforming the raw data into the frequency domain, filtering the transformed data, and deriving a plurality of acoustic characteristics from the filtered data. This can be performed by a petrophysical properties analyzing program stored in memory of the computer. The method can also include deriving petrophysical properties from the filtered data utilizing a petrophysical properties evaluation algorithm employable to predict one or more petrophysical properties of rock undergoing drilling.

Abstract: Apparatus, computer readable medium, and program code for identifying rock properties in real-time during drilling, are provided. An example of an embodiment of such an apparatus includes a downhole sensor subassembly connected between a drill bit and a drill string, acoustic sensors operably coupled to a downhole data interface, and a surface computer operably coupled to the downhole data interface.

Abstract: Methods of identifying rock properties in real-time during drilling, are provided. An example of method includes connecting a downhole sensor subassembly between a drill bit and a drill string, operably coupling acoustic sensors to a downhole processor, operably coupling a borehole telemetry system, downhole and surface data transmitting interfaces, and a surface computer to the downhole data transmitting interface. The method also includes receiving raw acoustic sensor data resulting from rotational contact of the drill bit with rock by the downhole processor, transforming the raw acoustic sensor data into the frequency domain, filtering the transformed data, and deriving acoustic characteristics from the filtered data. The method also includes the surface computer receiving the acoustic characteristics and deriving petrophysical properties from the acoustic characteristics directly or by utilizing a petrophysical properties evaluation algorithm.

Abstract: A method of maintaining a desired downhole pressure during a drilling operation can include measuring a parameter with a sensor, communicating actual parameter values from the sensor to a predictive device, training the predictive device to output predicted parameter values in response to input of the actual parameter values, and outputting the predicted parameter values from the predictive device when the predictive device ceases receiving the actual parameter values. A well drilling system can include a predictive device which outputs predicted parameter values in response to input of actual parameter values to the predictive device. The predictive device continues to output the predicted parameter values, even when the predictive device fails to receive valid actual parameter values. Another well drilling system includes a data validator which communicates valid actual parameter values to the predictive device, but does not communicate invalid actual parameter values to the predictive device.

Abstract: A system for measuring a resistivity parameter of an earth formation includes: at least one measurement electrode electrically connected to a first electrical source; at least one guard electrode; a shielding electrode interposed between the at least one guard electrode and the at least one measurement electrode, the shielding electrode being electrically connected to a second electrical source independent from the first electrical source, and the guard electrode being electrically connected to a third electrical source independent of the first and second electrical sources; at least one return electrode; insulators positioned between (i) the measurement electrode and the shielding electrode, (ii) the shielding electrode and the guard electrode and (iii) the measurement electrode, the guard electrode and the return electrode; and a processor configured to adjust at least one of the first electrical source and the second electrical source to minimize a current flow through the shielding electrode.

Abstract: A method for determining fracture geometry of a subterranean formation from radiation emitted from a fracture in the formation, including measuring gamma-radiation emitted from the fracture; subtracting background radiation from the measured gamma-radiation to obtain a peak-energy measurement; comparing the peak-energy measurement with a gamma-ray transport/spectrometer response model; and determining formation fracture geometry of the fracture in accordance with values associated with the response model.

Abstract: Acoustic velocities measured downhole are used to predict a rock strength using results of a regression analysis that include grain size. The grain size can be obtained from drill cuttings or from NMR measurements. The determined rock strength is used in drilling operations.

Abstract: A data acquisition module comprising a base sized and configured for disposition within a shank of a drill bit bore and an extension protruding therefrom having electrical contacts on an exterior surface thereof for connection to electrical contacts on an interior surface of a sub secured to the bit shank. A drill bit equipped with a data acquisition module, a bottom hole assembly including a drill bit bearing a data acquisition module operably coupled to a sub secured to the drill bit, and a method of transferring data from a data acquisition module carrying a data acquisition module to a sub secured to the drill bit.

Abstract: Method for identifying geologic features from geophysical or attribute data using windowed principal component (22), or independent component, or diffusion mapping (61) analysis. Subtle features are made identifiable in partial or residual data volumes. The residual data volumes (24) are created by (36) eliminating data not captured by the most prominent principal components (14). The partial data volumes are created by (35) projecting the data (21) on to selected principal components (22, 61). Geologic features may also be identified from pattern analysis (77) or anomaly volumes (62, 79) generated with a variable-scale data similarity matrix (73). The method is suitable for identifying physical features indicative of hydrocarbon potential.

Abstract: The invention is a method of developing a petroleum reservoir employing a technique for selection of the position of the wells to be drilled. A production indicator map is utilized comprising a set of cells each associated with a production indicator defining impact on fluid production of addition of a well in this cell. The production indicator map is constructed by selecting cells from among the set of cells of the map; determining production indicators in the selected cells; and interpolating the production indicators on the set of cells of the map, by an interpolation model accounting for a distance between the cell to be interpolated and the closest well to the cell to be interpolated. The position of the well to be drilled is defined by the cell where the production indicator is a maximum.

Abstract: A method of testing an earth formation can include incrementally opening a choke while drilling into the formation is ceased, thereby reducing pressure in a wellbore, and detecting an influx into the wellbore due to the reducing pressure in the wellbore. Another method of testing an earth formation can include drilling into the formation, with an annulus between a drill string and a wellbore being pressure isolated from atmosphere, then incrementally opening a choke while drilling is ceased, thereby reducing pressure in the wellbore, detecting an influx into the wellbore due to the reducing pressure in the wellbore, and determining approximate formation pore pressure as pressure in the wellbore when the influx is detected. Drilling fluid may or may not flow through the drill string when the influx is detected. A downhole pressure sensor can be used to verify pressure in the wellbore.

Abstract: A method for stimulating production of a first wellbore associated with a reservoir. The method includes determining a textural complexity of a formation in which the reservoir is located, determining an induced fracture complexity of the formation using the textural complexity, determining a first operation to perform within the formation to maintain conductivity of the formation based on the induced fracture complexity and the textural complexity, performing the first operation within the formation, and fracturing the formation to create a first plurality of fractures.