Abstract: A method for locating casing string joints using a measurement while drilling tool is disclosed. The method includes deploying an MWD tool in a wellbore and measuring the magnetic field along a length of the wellbore. Changes in the magnetic field along the length of the wellbore are evaluated to determine the location of at least one casing joint. Embodiments of this invention may be advantageously utilized, for example, in sidetracking operations to avoid milling through a casing joint. Use of this invention may obviate the need for a separate wireline run to locate the casing joints.

Abstract: A monitoring system for use with a horizontal directional drilling machine and adapted to determine the roll and/or pitch orientation of the downhole tool assembly by detecting signals from a sensor assembly supported by the downhole tool assembly. In a preferred embodiment, the monitoring system uses an antenna assembly to detect a signal transmitted from the sensor assembly. The antenna assembly transmits the detected signal to a processor which determines a calibration factor indicative of the actual orientation of the sensor relative to the known orientation of the downhole tool assembly. The processor then uses the calibration factor and the signal emitted from the sensor, indicative of the actual orientation of the sensor, to determine the actual orientation of the downhole tool assembly.

Abstract: A method for reducing vibration of a drilling tool assembly is disclosed. The method includes modeling the drilling tool assembly based on input parameters, simulating a vibration of a drill string coupled with a vibration of a drill bit, determining an initial total vibration from output parameters generated by the simulation, determining a location for at least one vibrational control device based on the initial total vibration to reduce the initial total vibration, and disposing the at least one vibrational control device on the drill string at the determined location.

Abstract: A method for communicating with a downhole device is provided. The method includes predefining an encoding language including codes understandable to the device, the codes represented in the language as predefined value combinations of drill string rotation variables such as rotation rate or duration. The method further includes rotating a drill string at first and second rates and measuring the rotation rates downhole. The first measured rotation rate is processed downhole in combination with the second measured rotation rate to acquire a code in the language at the downhole device. Embodiments of the invention are useful, for example, for transmitting commands from the surface to a downhole device such as a directional drilling tool. Exemplary embodiments of this invention advantageously provide for quick and accurate communication with a downhole device without substantially interrupting the drilling process.

Abstract: The present invention generally provides methods and apparatus for reducing noise in a detected electromagnetic wave used to telemeter data during a wellbore operation. In one embodiment, two surface antennae are placed on opposite sides of the wellbore and at the same distance from the wellbore. The signals from the two antennae are summed to reduce the noise in the electromagnetic signal transmitted from the electromagnetic downhole tool.

Abstract: A two-axis gyroscope used on a bottom hole assembly can be used for determining a rate of rotation about the rotational axis of a BHA. The method takes advantage of possible misalignment of at least one axis of the two axis gyroscope from orthogonality with respect to the rotational axis of the BHA, resulting in the misaligned gyro being sensitive to BHA rotation.

Abstract: A method for communicating with a downhole tool located in a subterranean borehole is disclosed. Exemplary embodiments of the method include encoding data and/or commands in a sequence of varying drill string rotation rates and drilling fluid flow rates. The varying rotation rates and flow rates are measured downhole and processed to decode the data and/or the commands. In one exemplary embodiment, commands in the form of relative changes to current steering tool offset and tool face settings are encoded and transmitted downhole. Such commands may then be executed, for example, to change the steering tool settings and thus the direction of drilling. Exemplary embodiments of this invention advantageously provide for quick and accurate communication with a downhole tool.

Abstract: A method and apparatus for providing a local response to a local condition in an oil well are disclosed. A sensor is provided to detect a local condition in a drill string. A controllable element is provided to modulate energy in the drill string. A controller is coupled to the sensor and to the controllable element. The controller receives a signal from the sensor, the signal indicating the presence of said local condition, processes the signal to determine a local energy modulation in the drill string to modify said local condition, and sends a signal to the controllable element to cause the determined local energy modulation.

Abstract: A system and method estimates the distance between a borehole and a subsurface boundary of interest in a geophysical region. In one embodiment, available existing sensor data for the geophysical region is used to create a resistivity model of the region, with the model reflecting changes in resistivity across the boundary. A hypothetical borehole has a number of segments along its length that are spaced-apart from the boundary by different, preselected distances. The ratio between two selected resistivity curves in each of the respective spaced-apart segments is computed, and these ratio values are plotted as a function of distance from the boundary. A curve-fitting algorithm is applied to derive an equation, which may be applied to actual sensor data from a sensor package.

Abstract: A method and apparatus for use in assessing down-hole drilling conditions are disclosed. The apparatus includes a drill string, a plurality of sensors, a computing device, and a down-hole network. The sensors are distributed along the length of the drill string and are capable of sensing localized down-hole conditions while drilling. The computing device is coupled to at least one sensor of the plurality of sensors. The data is transmitted from the sensors to the computing device over the down-hole network. The computing device analyzes data output by the sensors and representative of the sensed localized conditions to assess the down-hole drilling conditions. The method includes sensing localized drilling conditions at a plurality of points distributed along the length of a drill string during drilling operations; transmitting data representative of the sensed localized conditions to a predetermined location; and analyzing the transmitted data to assess the down-hole drilling conditions.

Abstract: Systems for implementing methods for generating platform location sets comprising selecting a set of platform locations; determining additional platform locations to add to the set of platform locations; validating the additional platform locations, and determining an optimum location for each platform location in the set of platform locations.

Abstract: A method for designing a closed-chamber drillstem test system. Parameters of available equipment and a well to be tested are collected. Initial or proposed chamber size and chamber pressurizing fluids are then selected. A simulation of a test is then performed. The simulation is performed in time increments, with pressure in the well assumed to be static during each time increment. Calculated flow volume from the formation during each increment is used to adjust pressure in the well for the next increment. The process is continued until the test would be considered complete based on an optimization parameter. If the total simulated time to complete the test is not in a desirable range, the initial chamber parameters are changed and the simulation is run again. The process is repeated until the simulated test time reaches a desirable range.

Abstract: A system for determining the ability of a selected motor to function in a wellbore preferably includes an input device, a data storage device and a program. The program is preferably configured to determine an expected motor load based on motor input data and application input data. Using the expected motor load, the program determines a projected motor temperature increase. The program adds the projected motor temperature increase with the wellbore temperature to determine a projected operating temperature. The projected operating temperature is compared with the maximum recommended operating temperature of the selected motor, or a list of candidate motors, to determine the ability of the selected motor to function in the wellbore.

Abstract: The present invention is a method of interpreting sampled mud gas compositional and isotopic data from a target area in a drilling operation. The compositional and isotopic data is plotted on a chart. The chart preferably illustrates methane compositional data together with isotopic composition, such as ?13C1. From this chart, mixing lines are determined. The mixing lines are determined by finding data points plotted on the chart which approximate a straight line or other trend. The mixing lines are then analyzed to determine reservoir isotopic signature, hydrocarbon communication and any interference to this communication within the target area.

Abstract: This invention provides an automatic control system and method for bottom hole pressure (BHP) in the underbalanced drilling. It relates to a computer automatic control technology. The automatic control system according to the invention includes a processing module for the BHP based on the mechanisms of hydraulics. The BHP in the underbalanced drilling is calculated from the acquired standpipe pressure (SPP), the calculated circulating pressure loss in the drilling tools, drill bit pressure drop and the fluid colunm pressure in the drill string. The resulting BHP is then compared with the set pressure value of the system. In case that the BHP is higher or lower than the set pressure, an instruction to regulate throttle valve opening will be issued in order to bring the BHP back to the set pressure range and complete BHP monitoring and control.

Abstract: A method for optimizing drilling parameters includes obtaining previously acquired data, querying a remote data store for current well data, determining optimized drilling parameters, and returning optimized parameters for a next segment to the remote data store. Determining optimized drilling parameters may include correlating the current well data to the previously acquired data, predicting drilling conditions for the next segment, and optimizing drilling parameters for the next segment.

Abstract: A method for simulating a drilling tool assembly having a drill string and a drill bit. The method includes simulating a dynamic response of the drill string; simulating a dynamic response of the drill bit; and resolving the dynamic response of the drill string and the dynamic response of the drill bit into a dynamic response of the drilling tool assembly.

Abstract: A control method for use with a steerable drilling system comprises the steps of inputting parametric model data representative of drilling conditions and using the data to determine achievable drilling directions.

Abstract: A method of characterizing a borehole traversing an earth formation including (a) obtaining an array of data from a formation characterization tool, wherein the data describes a section of the borehole; (b) computing at least one spatial characteristic describing the relative position of pairs of data; (c) assigning said pairs of data to bins based on the spatial characteristic, wherein the size of the bins are selected based on the tool; (d) transforming the data to petrophysical properties of the borehole; (e) calculating the variance of each bin; (f) developing a model of the variances; (g) determining at least one geostatistical parameter using the model; and (h) upscaling the geostatistical parameters to characterize a region of said earth formation. The method may further include generating a heterogeneity index log using the geostatistical model parameters. The method may be implemented using a computer program product for processing and interpreting borehole data.

Abstract: A method and system is disclosed for automatically detecting the state of a drilling rig during the drilling process of a wellbore. Two or more, but preferably four independent input data channels are received, each input data channel representing a series of measurements made over time during the drilling process. Based on the input channels the most likely state of the drilling rig is detected from at least three possible rig states. The detection method is preferably probabilistic and even more preferably based on particle filtering techniques. The preferred systems and methods disclosed are also capable of detecting events and displaying or notifying drilling personnel of the detected events and suggesting corrective action.

Abstract: A method of interpreting mud gas samples in a drilling operation of a target area. The method starts with obtaining a plurality of mud gas samples at a plurality of incremental depths of the target area. The plurality of mud gas samples are analyzed to find various isotopic data at each depth. The isotopic data of the mud gas samples are plotting on several charts to provide a visual representation of the isotopic data trends. The charts may include: depth versus ethane/methane; depth versus ?13C per mil; and depth versus ?13C and gas show. In addition, the percentage methane versus ?13C is provided on a separate chart. This percentage methane versus ?13C chart provides engineering and geological information such as the location of lithological hydrocarbon seals, barriers, and zones of good hydrocarbon communication (e.g., compartments). This engineering and geological information is then correlated with the other charts.

Abstract: 3D seismic classification is a breakthrough technology to determine the three-dimensional distribution of pore fluid, lithology, and faults/fractures from multiple seismic attribute volumes. This method provides an innovative, timesaving solution for identification and definition of drilling targets, especially in areas with multiple pay zones and complex geology.

Abstract: A method of evaluating the capillary pressure curve of rocks of an underground reservoir from measurements on rock debris or fragments such as cuttings from the reservoir, over the total saturation range of these rocks, within a short period and at a low cost, from these measurements is disclosed. The method comprises measuring the permeability k of the debris, measuring the capillary pressure curve Pc as a function of the saturation of these fragments initially saturated with a fluid (brine for example) by subjecting them to centrifugation, and parametrizing a capillary pressure curve Pc satisfying empirical relations depending on adjustable parameters, constrained to adjust to an asymptotic part of the capillary curve measured by centrifugation, and to the value of permeability k measured on the cuttings, so as to obtain the whole of the capillary pressure curve. Applications include hydrocarbon reservoir evaluation.

Abstract: An iterative drilling simulation method and system for enhanced economic decision making includes obtaining characteristics of a rock column in a formation to be drilled, specifying characteristics of at least one drilling rig system; and iteratively simulating the drilling of a well bore in the formation. The method and system further produce an economic evaluation factor for each iteration of drilling simulation. Each iteration of drilling simulation is a function of the rock column and the characteristics of the at least one drilling rig system according to a prescribed drilling simulation model.

Abstract: Methods and apparatuses to determine the rate of penetration of a subterranean drilling assembly into a formation are disclosed. The methods and apparatuses generate rate of penetration by integration axial acceleration data with respect to time and applying a correction factor. The correction factor, meant to account for the effect of gravity on the acceleration data, is determined when rotational velocity of the drilling assembly relative to the formation is zero.

Abstract: Methods and systems for controlling the drilling of a borehole are disclosed. The methods employ the assumption that nonlinear problems can be modeled using linear equations for a local region. Common filters can be used to determine the coefficients for the linear equation. Results from the calculations can be used to modify the drilling path for the borehole. Although the calculation/modification process can be done continuously, it is better to perform the process at discrete intervals along the borehole in order to maximize drilling efficiency.

Abstract: A method and apparatus for predicting the performance of a drilling system for the drilling of a well bore in a given formation includes generating a geology characteristic of the formation per unit depth according to a prescribed geology model, obtaining specifications of proposed drilling equipment for use in the drilling of the well bore, and predicting a drilling mechanics in response to the specifications as a function of the geology characteristic per unit depth according to a prescribed drilling mechanics model. Responsive to a predicted-drilling mechanics, a controller controls a parameter in the drilling of the well bore. The geology characteristic includes at least rock strength. The specifications include at least a bit specification of a recommended drill bit. Lastly, the predicted drilling mechanics include at least one of bit wear, mechanical efficiency, power, and operating parameters.

Abstract: A method to create a drilling performance assessment ratio. The ratio includes the steps of establishing a technical minimum time limit standard for each of multiple sequential steps required for a drilling operation. Actual time performance for each of the multiple steps is measured for an actual drilling operation. The actual performances are compared to the technical time limit standards in order to produce a drilling performance ratio.

Abstract: A method for determining formation pressure at a depth region of formations surrounding a borehole, including: keeping track of the time since cessation of drilling at the depth region; deriving formation permeability at the depth region; causing wellbore pressure to vary periodically in time and determining, at the depth region, the periodic and non-periodic component of pressure measured in the formations; determining, using the time, the periodic component and the permeability, the formation pressure diffusivity and transmissibility and an estimate of the size of the pressure build-up zone around the wellbore at the depth region; determining, using the time, the formation pressure diffusivity and transmissibility, and the non-periodic component, the leak-off rate of the mudcake at the depth region; determining, using the leak-off rate, the pressure gradient at the depth region; and extrapolating, using the pressure gradient and the size of the build-up zone, to determine the formation pressure.

Abstract: A method for estimating an azimuthal dependence of a parameter of a borehole using logging sensor measurements acquired as a function of azimuth of the logging sensors is provided. The method includes acquiring at least one logging sensor measurement and a corresponding azimuth from a downhole tool. The method further includes processing a convolution of the logging sensor measurement and corresponding azimuth with a predetermined window function to determine convolved logging sensor data for at least one azimuthal position. Certain embodiments of this invention may be advantageously utilized in LWD imaging applications to provide for superior image resolution and noise rejection as compared to prior art imaging techniques.

Abstract: A method for displaying a bottom-hole assembly together with a borehole trajectory includes displaying the borehole trajectory in a display window; and displaying the bottom-hole assembly in the display window such that the borehole trajectory and the bottom-hole assembly are in parallel and a measurement depth of the bottom-hole assembly corresponds to a measurement depth of the borehole trajectory.

Abstract: A method for improving drilling performance of a drilling tool assembly is disclosed. The method includes identifying a drilling performance parameter to be improved. One or more potential solutions are defined to improve the drilling performance parameter. A drilling simulation is performed to determine the dynamic response of the drilling tool assembly during a drilling operation. Determining the dynamic response includes determining the interaction of a cutting element of a drill bit with an earth formation. Improvement in the drilling performance parameter is determined based upon the drilling simulation.

Abstract: A method is disclosed for characterizing a drilling hazard. The method includes determining a well plan including at least a wellbore trajectory. A likelihood of occurrence of at least one drilling hazard is estimated. A severity of the at least one drilling hazard is estimated. The hazard is displayed on a representation of the wellbore trajectory, by indicating thereon a position of, the likelihood and the severity of the at least one drilling hazard.

Abstract: An inverse analysis method for characterizing diffusion of vapor from an underground source of volatile contaminant using data taken by an in-situ sensor. The method uses one-dimensional solutions to the diffusion equation in Cartesian, cylindrical, or spherical coordinates for isotropic and homogenous media. If the effective vapor diffusion coefficient is known, then the distance from the source to the in-situ sensor can be estimated by comparing the shape of the predicted time-dependent vapor concentration response curve to the measured response curve. Alternatively, if the source distance is known, then the effective vapor diffusion coefficient can be estimated using the same inverse analysis method. A triangulation technique can be used with multiple sensors to locate the source in two or three dimensions. The in-situ sensor can contain one or more chemiresistor elements housed in a waterproof enclosure with a gas permeable membrane.

Abstract: Disclosed is a system and method for directing data representing well operations (drilling and producing) through the Internet or similar wide area network. The instant invention comprises a system and method of installing sensors at the well to provide technical information to remotely-located Internet users who provide services to the well owner. The service providers may be observers, who may then advise the well owners and operators as to actions to take to increase or optimize well performance. Service providers may also be data storage companies, who clean and store the data from the well. Service providers may then be paid from a portion of the well revenues or a portion of the incrementally-increased revenues.

Abstract: The aim of the present invention is the determination of the best possible correlation (keying) for electric recordings obtained in a borehole with seismic recordings obtained in a volume of subsoil (the seismic block) containing the bore. This is accomplished by defining in a neighborhood of the trajectory of the bore a set of layered networks, the entries of which are the seismic signals and the exits of which are electric signals. Accordingly, a quality measure is awarded with regard to the convergence. The best convergence quality then permits the determination of the best place in the neighborhood which produces the best keying.

Abstract: An apparatus and method is disclosed for modeling an electric submersible pump using a neural network, data from a deterministic model, and, optionally, data obtained from a real world electric submersible pump. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Abstract: A self-adaptable data compression technique includes compressing the digital data points of a waveform according to at least a first protocol and a second protocol, and various comparing the compressed data under various protocols to determine which would require the least memory for storage.

Abstract: Systems provide for electronic development of a bore plan for use in connection with an underground boring machine. Electronically developing a bore plan involves providing topographical information representative of topography of the bore site and providing bore path information representative of an intended bore path for the bore site. The bore path information includes at least two target points through which the intended bore path is to pass. The intended bore path can define a pilot bore path or a backream path. The target points comprise an entry point and an exit point, and each of the target points is defined by at least a distance value, lateral value, and a depth value.

Abstract: A system and method for controlling an HDD machine to move a cutting tool along an underground path in accordance with a pre-established bore plan. Cutting tool movement is detected from above-ground. During HDD machine operation, one or more control programs are accessed. Each of the control programs can cause the HDD machine to execute a sequence of pre-defined HDD machine actions. A particular control program of the one or more control programs is executed to augment movement of a drill pipe or the cutting tool.

Abstract: Systems and methods for determining a formation property related to formation strength and stresses are disclosed. A method for determining a formation strength includes obtaining radial formation property measurements at different wellbore pressures; generating a radial stress profile based on a formation model; generating a radial stress function from the radial stress profile; and comparing the radial formation property measurements with the radial stress function to determine the formation strength. A method for determining a formation stress profile includes deriving formation parameters from a formation radial profiling; obtaining formation log data that comprise formation density data; estimating formation stresses from the formation log data; and deriving a radial stress profile based on a formation model, the derived formation parameters, and the estimated formation stresses.

Abstract: An automated method and system for determining the state of a drilling or other suitable well operations includes storing a plurality of states for the well operation. Mechanical and hydraulic data is received for the well operation. Based on the mechanical and hydraulic data, one of the states is automatically selected as the state of the well operation. Process evaluation may be performed based on the state of the well operation.

Abstract: A nonlinear iterative deconvolution method and system. In one embodiment, the system comprises a data acquisition module, a storage module, and a processing module. The data acquisition module obtains logging data from measurements made by a sensor tool moving through a borehole, and stores the logging data in the storage module. The processing module processes the logging data to determine a formation model by iteratively updating a set of formation model values which correspond to a set of positions along the borehole. The iterative updating includes (i) calculating an error value; and (ii) applying a linearizing factor to the error value. The iterative updating may be expressible as a weighted sum of a current formation model value with a product of the error value and the linearizing factor. The iterative updating may continue until an adequate match between the logging data and a calculated tool response is achieved.

Abstract: A method for determining rotational offset between first and second gravity measurement devices deployed on a downhole tool is disclosed. The method includes positioning the tool in a previously surveyed section of a borehole that provides a historical survey including at least three previously surveyed azimuthal reference points and utilizing the gravity measurement devices to determine local azimuths at three or more sites in the previously surveyed section of the borehole. The method further includes comparing local azimuths with the historical survey and determining a rotational offset between the measurement devices that gives a best fit between local azimuths and the historical survey. A system adapted to execute the disclosed method and a computer system including computer-readable logic configured to instruct a processor to execute the disclosed method are also provided.

Abstract: A method for simulating the drilling performance of a roller cone bit drilling an earth formation may be used to generate a visual representation of drilling, to design roller cone drill bits, and to optimize the drilling performance of a roller cone bit. The method for generating a visual representation of a roller cone bit drilling earth formations includes selecting bit design parameters, selecting drilling parameters, and selecting an earth formation to be drilled. The method further includes calculating, from the bit design parameters, drilling parameters and earth formation, parameters of a crater formed when one of a plurality of cutting elements contacts the earth formation. The method further includes calculating a bottomhole geometry, wherein the crater is removed from a bottomhole surface.

Abstract: The present invention generally provides methods of geological analysis. The method includes collecting wellbore data from a well undergoing underbalanced drilling. The wellbore data is then correlated to a seismic data to predict geological properties away from the wellbore. In one embodiment, correlating the seismic data with the wellbore data involves converting the seismic data and the wellbore data to a one-dimensional numerical series, respectively. The two respective one-dimensional numerical series are compared to each other to produce a mathematical formulation relating the two series. In another embodiment, the wellbore data may be separated into different categories or classifications and individually compared to the seismic data. Preferably, the categories are compared to two or more variations of seismic data and their attributes to derive at unique “signatures” for the respective category. The signatures may then be used to produce “classification” maps of the wellbore data.

Abstract: A method for displaying a borehole trajectory includes displaying the borehole trajectory and an indicator of a working interval in a big view window; and displaying a section of the borehole trajectory in a small view window, wherein the section corresponds to the working interval. The method may further includes displaying well log data in a log view window. A system for displaying a borehole trajectory includes a display; and a computer operatively coupled to the display, the computer having a program to display the borehole trajectory on the display, the program comprising instructions to enable: displaying the borehole trajectory and an indicator of a working interval in a big view window; and displaying a section of the borehole trajectory in a small view window, wherein the section corresponds to the working interval.

Abstract: This invention provides a measurement-while-drilling (MWD) downhole assembly for use in drilling boreholes which utilizes gyroscopes, magnetometers and accelerometers for determining the borehole inclination and azimuth during the drilling of the borehole. With the present invention, a secondary borehole for secondary recovery operations may be drilled with accuracy in proximity to a cased producing borehole.

Abstract: A method is provided for estimating the positional uncertainty in drilling a well such as an oil well. A first set of values is supplied representing a first three-dimensional uncertainty of the actual position of a drill bit with respect to the estimated position. A second set of values is supplied representing a second three-dimensional uncertainty of the actual position of a geological feature with respect to the estimated position thereof. For example, the first set of values relates to positional uncertainties because of the drilling procedure whereas the second set of uncertainties is associated with the obtaining and interpretation of seismic data. The first and second sets of values are combined to form a third set of values which represents a third uncertainty of the position of the drill bit with respect to the geological feature.

Abstract: A real-time method is disclosed for maintaining subterranean formation stability through monitoring the interaction between the formation and fluids introduced into (or produced from) a wellbore penetrating the formation. The method employs real-time wellbore (in)stability logging methodology. The method is exemplified by a Pore Pressure Transmission (PPT) test. In such test, test fluids are exposed to Pierre II shales (20% w/w NaCl solution and sodium silicate fluid with 20% w/w NaCl, for example) in a PPT apparatus. Membrane efficiency of the two fluids when exposed to the outcrop shale is calculated, and based on the simultaneous acquisition of acoustic data, estimation of a dynamic rock property is made.