摘要:
An apparatus and method for estimating a parameter of interest of an earth formation involving alignment information between non-collocated oriented receivers and their corresponding non-collocated oriented transmitters. The method may include generating signal responses indicative to energy transmitted into an earth formation; estimating differences in alignment between transmitters and receivers; using the estimated differences in alignment to compensate for misalignment; and estimating a parameter of interest using the misalignment compensated signals. The misalignment estimate may include an inversion of at least one measurement from an alignment sensor. The apparatus may include a bottom hole assembly with oriented transmitters, oriented receivers, one or more alignment sensors, and at least one processor configured to compensate for misalignment using information about difference in alignment between at least one oriented transmitter and at least one oriented receiver.
摘要:
An apparatus and method for estimating a parameter of interest of an earth formation involving alignment information between non-collocated oriented receivers and their corresponding non-collocated oriented transmitters. The method may include generating signal responses indicative to energy transmitted into an earth formation; estimating differences in alignment between transmitters and receivers; using the estimated differences in alignment to compensate for misalignment; and estimating a parameter of interest using the misalignment compensated signals. The misalignment estimate may include an inversion of at least one measurement from an alignment sensor. The apparatus may include a bottom hole assembly with oriented transmitters, oriented receivers, one or more alignment sensors, and at least one processor configured to compensate for misalignment using information about difference in alignment between at least one oriented transmitter and at least one oriented receiver.
摘要:
A transmitter on a bottomhole assembly (BHA) is used for generating a transient electromagnetic signal in an earth formation. A processor estimates the distance to a resistivity interface using a signal produced by a receiver on the BHA. The transmitter-receiver distance may be less than 1 m. The estimation of the distance is done in real time using a thin conductive sheet approximation.
摘要:
A transmitter on a bottomhole assembly (BHA) is used for generating a transient electromagnetic signal in an earth formation. A processor estimates the distance to a resistivity interface using a signal produced by a receiver on the BHA. The transmitter-receiver distance may be less than 1 m. The estimation of the distance is done in real time using a thin conductive sheet approximation.
摘要:
An apparatus and method for calibrating a multi-component induction logging tool. The method may include orienting a Z-transmitter coil to be substantially orthogonal to at least one Z-receiver coil, positioning an X-transmitter coil disposed on the logging tool so that the X-transmitter coil is substantially parallel to a conducting surface; encompassing the Z-transmitter coil, the X-transmitter coil, and at least one Z-receiver coil of the logging tool with at least one conducting loop of a calibrator; and calibrating the logging tool using the calibrator. The apparatus may include a calibrator configured to receive the logging tool. The Z-transmitter coil and the Z-receiver coil may be located on separate subs that are detachable from one another.
摘要:
A method for identifying drilling induced fractures while drilling a wellbore into a formation is disclosed. The method includes: obtaining multi-component induction data collected by a drill string including a multi-component induction tool; processing the data to estimate values for principal components; and identifying drilling induced fractures from the principal components. An instrument and a computer program product are disclosed.
摘要:
A multicomponent induction logging tool uses a nonconducting mandrel. A central conducting member including wires that electrically connect at least one of the antennas to another of the antennas. Electrodes disposed about the transmitter antenna form a conductive path through a borehole fluid to the central conducting member.
摘要:
Measurements made by a multi-component induction logging tool are corrected for tool eccentricity in a deviated borehole. The eccentricity angle is determined from single frequency skin-effect corrected data and is then used to correct multifrequency data. Multifrequency focusing is then applied to the corrected multifrequency data. An inversion is then used to recover formation resistivity and relative dip and azimuth of the borehole.
摘要:
A transmitter on an instrument is used to induce currents in an earth formation when it is turned on or off. A Fourier transform is applied to transient measurements made in the receivers. A multifrequency focusing of the transformed data is used for applications like determination of a distance to an interface in the formation, controlling the drilling direction, determination of formation resistivities and formation strike directions.
摘要:
A multicomponent induction logging tool uses a nonconducting mandrel. A central conducting member including wires that electrically connect at least one of the antennas to another of the antennas. Electrodes disposed about the transmitter antenna form a conductive path through a borehole fluid to the central conducting member.