4765results about "Electric/magnetic detection for well-logging" patented technology

A Flogrid Simulation Gridding Program includes a Flogrid structured gridder. The structured gridder includes a structured areal gridder and a block gridder. The structured areal gridder will build an areal grid on an uppermost horizon of an earth formation by performing the following steps: (1) building a boundary enclosing one or more fault intersection lines on the horizon, and building a triangulation that absorbs the boundary and the faults; (2) building a vector field on the triangulation; (3) building a web of control lines and additional lines inside the boundary which have a direction that corresponds to the direction of the vector field on the triangulation, thereby producing an areal grid; and (4) post-processing the areal grid so that the control lines and additional lines are equi-spaced or smoothly distributed. The block gridder of the structured gridder will drop coordinate lines down from the nodes of the areal grid to complete the construction of a three dimensional structured grid. A reservoir simulator will receive the structured grid and generate a set of simulation results which are displayed on a 3D Viewer for observation by a workstation operator.

A method of managing a fluid or gas reservoir is disclosed which assimilates diverse data having different acquisition time scales and spatial scales of coverage for iteratively producing a reservoir development plan that is used for optimizing an overall performance of a reservoir. The method includes: (a) generating an initial reservoir characterization, (b) from the initial reservoir characterization, generating an initial reservoir development plan, (c) when the reservoir development plan is generated, incrementally advancing and generating a capital spending program, (d) when the capital spending program is generated, monitoring a performance of the reservoir by acquiring high rate monitor data from a first set of data measurements taken in the reservoir and using the high rate monitor data to perform well-regional and field-reservoir evaluations, (e) further monitoring the performance of the reservoir by acquiring low rate monitor data from a second set of data measurements taken in the reservoir, (f) assimilating together the high rate monitor data and the low rate monitor data, (g) from the high rate monitor data and the low rate monitor data, determining when it is necessary to update the initial reservoir development plan to produce a newly updated reservoir development plan, (h) when necessary, updating the initial reservoir development plan to produce the newly updated reservoir development plan, and (i) when the newly updated reservoir development plan is produced, repeating steps (c) through (h). A detailed disclosure is provided herein relating to the step (a) for generating the initial reservoir characterization and the step (b) for generating the initial reservoir development plan.

A transmitter antenna assembly for transient electromagnetic well logging instrument comprises an antenna coil coupled with a current source and a magnetic core having residual magnetization. Switching current in the antenna coil results in magnetization reversal in the magnetic core and change in magnetic dipole moment of the antenna. After the magnetization reversal is complete the current is removed and the new vector of magnetic dipole of the antenna maintains constant (steady-state phase of the antenna dipole) due to magnetic hysteresis of magnetic material employed for the magnetic core. No power expenditure during the steady-state phase of the magnetic dipole facilitates highly effective generation and fast switching of a large magnetic dipole. The magnetic core also serves as a shield between the antenna coil and any conductive part of the antenna assembly. Embodiments suitable for measurement-while-drilling or measurements through casing make use of residual magnetization of magnetic drill collar or magnetic casing respectively.

This invention is directed to a downhole method and apparatus for simultaneously determining the horizontal resistivity, vertical resistivity, and relative dip angle for anisotropic earth formations. The present invention accomplishes this objective by using an antenna configuration in which a transmitter antenna and a receiver antenna are oriented in non-parallel planes such that the vertical resistivity and the relative dip angle are decoupled. Preferably, either the transmitter or the receiver is mounted in a conventional orientation in a first plane that is normal to the tool axis, and the other antenna is mounted in a second plane that is not parallel to the first plane. This invention also relates to a method and apparatus for steering a downhole tool during a drilling operation in order to maintain the borehole within a desired earth formation. The steering capability is enabled by computing the difference or the ratio of the phase-based or amplitude-based responses of the receiver antennas which are mounted in planes that are not parallel to the planes of the transmitter antennas. Although this invention is primarily intended for MWD or LWD applications, this invention is also applicable to wireline and possibly other applications.

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.

A novel on-the-fly data processing technique is useful for extracting signals from the azimuthal variation of the directional measurements acquired by a logging tool within a borehole. The relevant boundary, anisotropy and fracture signals are extracted from the formation response through fitting of the azimuthal variation of the measured voltages to some sinusoidal functions. The orientation of the bedding is also obtained as a result. The extracted directional signals are useful for obtaining boundary distances and making geosteering decisions. Two techniques involving inversion and cross-plotting may be employed, depending on the nature of the boundary. A Graphical User Interface (GUI) is part of a system to facilitate flexible definition of inversion objectives, for improving the inversion results, and for visualization of the formation model as well as inversion measurements.

Methods and apparatus for making directional measurements of earth formations surrounding a borehole. New antenna coil shield designs are utilized to provide selective attenuation of at least one electromagnetic energy field component as the component interacts with the shield. The new shields are implemented in several downhole tool configurations to provide azimuthally focused formation measurements. In effect, the new shield filters interacting electromagnetic energy field components to pass those components corresponding to a magnetic dipole oriented at an angle from the tool axis. The shields thereby alter a coil's envelope of influence to electromagnetic energy. The new shields also form part of a system for making directional measurements while drilling.

A method is disclosed for compressing a frame of data representing parameter values, a time at which each parameter value was recorded, and an orientation of a sensor at the time each parameter value was recorded. Generally the method includes performing a two-dimensional transform on the data in the orientation domain and in a domain related to the recording time. In one embodiment, the method includes calculating a logarithm of each parameter value. In one embodiment, the 2-D transform includes generating a Fourier transform of the logarithm of the parameter values in the azimuthal domain, generating a discrete cosine transform of the transform coefficients in the time domain. This embodiment includes quantizing the coefficients of the Fourier transform and the discrete cosine transform. One embodiment of the method is adapted to transmit resistivity measurements made by an LWD instrument in pressure modulation telemetry so that while-drilling images of a wellbore can be generated. The one embodiment includes encoding the quantized coefficients, error encoding the encoded coefficients, and applying the error encoded coefficients to the pressure modulation telemetry.

A directional induction logging tool is provided for measurement while drilling. This tool is preferably placed in a side pocket of a drill collar, and it comprises transmitter and receiver coils and an electromagnetic reflector. The reflector, which may be a layer of highly conductive material placed between the coils and the body of the drill collar, serves to focus the electromagnetic fields generated and sensed by the tool in the direction away from the reflector, thus providing a directional response to formation conductivity with a relatively high depth of investigation. In preferred embodiments of the invention, magnetically permeable cores are placed within the coils to concentrate the magnetic fields that pass through them. Circuitry is described for balancing the mutual inductive coupling of the coils by injecting a direct current signal through one or more of the coils, which alters the magnetic permeability of the core material. The magnitude of the direct current required to achieve a balanced condition may be derived from the quadrature phase component of the return signal. Circuitry is also provided for generating a transmitted signal and for processing the return signals, including digital-to-analog conversion circuitry for providing digital data for transmission to the surface. This tool may be employed to provide real-time directional conductivity information that may be used to detect and follow bed boundaries in geosteering operations.

A method, apparatus, and program storage device for integrating and implementing rule-based, heuristic, wellbore key performance rate of penetration indicators advising drilling operations personnel based on the situational awareness of trended earth properties and real time wellbore sensor data, is disclosed.

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. The method also includes incrementally rotating the bit and repeating the calculating of crater parameters and bottomhole geometry based on calculated roller cone rotation speed and geometrical location with respect to rotation of said roller cone drill bit about its axis. The method also includes converting the crater and bottomhole geometry parameters into a visual representation.

An electromagnetic imaging method for electromagnetically measuring physical parameters of a pipe CJ, CC by means of a plurality of measuring arrangement ZMA, MCMA, MonMa, ImMA comprising a plurality of transmitter coil ZTX, LFTX, DTX and a plurality of receiver coil ZRX1, ZR2, MRX, MC, PRX1, PRX2, PRX3, PRX4, PRX5, PRX6, PRX7, PRX8, PRX9, PRX10, PRX11, PRX12, PRX13, PRX14, PRX15, PRX16, PRX17, PRX18, the transmitter coils and receiver coils being associated so as to form the plurality of measuring arrangement, the plurality of measuring arrangement being adapted to be positioned into the pipe and displaced through the pipe, the physical parameters being measured for a plurality of position along the pipe, the method comprising the steps of:

• a) determining a first value of an average ratio of magnetic permeability to electrical conductivity and a first value of an average inner diameter of the pipe Z-MES,
• b) determining an average electromagnetic thickness of the pipe MC-MES,
• c) determining a second value of the average ratio of magnetic permeability to electrical conductivity and a second value of the average inner diameter of the pipe Mon-MES according to excitation frequencies which are substantially lower than the excitation frequencies used to determine the first values Z-MES,
• d) determining a first image EMTIM of the pipe electromagnetic thickness and the pipe defects Im-MES,
• e) discriminating the defects at an inside perimeter of the pipe from the defects at an outside perimeter of the pipe Dis-MES, and
• f) forming a corrected first image IOFIM of the pipe taking into account a position of the defects.

The present invention discloses a method and system compensating for thermally induced motion of probe cards used in testing die on a wafer. A probe card incorporating temperature control devices to maintain a uniform temperature throughout the thickness of the probe card is disclosed. A probe card incorporating bi-material stiffening elements which respond to changes in temperature in such a way as to counteract thermally induced motion of the probe card is disclosed including rolling elements, slots and lubrication. Various means for allowing radial expansion of a probe card to prevent thermally induced motion of the probe card are also disclosed. A method for detecting thermally induced movement of the probe card and moving the wafer to compensate is also disclosed.

A method is provided for determining an electric conductivity of an earth formation formed of different earth layers, which earth formation is penetrated by a wellbore containing a wellbore fluid, is provided. The method includes the steps of: lowering an induction logging tool into the wellbore to a location surrounded by a selected one of the earth layers, the tool having a magnetic field transmitter effective to induce magnetic fields of different frequencies in the earth formation, and a magnetic field receiver effective to receive response magnetic fields and to provide a signal representative of each response magnetic field, at least one of the transmitter and the receiver having a plurality of magnetic dipole moments in mutually orthogonal directions. At least two of the different frequencies are selected, and for each selected frequency, the transmitter is operated so as to induce a magnetic field in the earth formation and the receiver is operated so as to provide a signal representing a response magnetic field, wherein the at least one of the transmitter and receiver is operated in the mutually orthogonal directions. The signals are combined in a manner so as to create a combined signal having a reduced dependency on the electric conductivity in the wellbore region. The formation resistivity and the relative orientation of the logging tool with respect to the formation layering is determined from the combined signal.

A method is disclosed for generating a wellsite design, comprising: designing a workflow for an Earth Model; building an initial Earth Model based on the workflow adapted for modeling drilling and completions operations in a hydrocarbon reservoir; calibrating the initial Earth Model thereby generating a calibrated Earth Model; and generating the wellsite design using the calibrated Earth Model.

A method and apparatus for evaluating the resistivity of earth formations surrounding a borehole, particularly high-contrast thin-layer formations or at high dip angles. The method involves positioning a pair of transmitters and a pair of receivers within the borehole, the receivers or transmitters adhering to specific spacing limitations, alternately transmitting electromagnetic energy of a particular frequency and receiving voltage data associated with the transmitted energy. Multiple voltage data are acquired and a representation of a resistivity or conductivity profile is created from a formulated difference of the data from a particular depth and/or neighboring depths. The apparatus forms part of a well logging system including a well tool adapted to be moveable through a borehole. The apparatus being coupled to the well tool and adapted with means to input voltage data developed by the receivers disposed on the well tool. The apparatus further adapted with means for performing calculations to determine a conductivity profile and for recording the profile on an output record medium.

A process to determine optimal completion type and design prior to drilling of a hydrocarbon producing well utilizing information from hydrocarbon recovery modeling such as reservoir, geo-mechanical, and material modeling over the production life of the well. An embodiment of the process includes obtaining information regarding pore pressure depletion, stress magnitudes and orientations, and strength of rock formation from hydrocarbon recovery modeling to determine optimum well completion design including the selection of a completion type, trajectory, and location. Additionally, the process may also consider probable failure mechanisms and identified completion requirements, and their corresponding effect on completion options.