Abstract: A method for real-time formation assessment using a multi-component induction logging tool includes conveying a multi-component induction (MCI) logging tool along a borehole through a formation. The method further includes determining a relative dip and a relative azimuth of the formation based on data from the MCI logging tool. The method further includes calculating true dip and true azimuth of the formation based on the relative dip and the relative azimuth. The method further includes assessing the quality of the true dip and the true azimuth calculations.

Abstract: In some aspects, systems and methods are provided for determining formation properties using data from both a high-frequency dielectric tool (HFDT) and an array induction tool (AIT). The system includes a controller in communication with at least one HFDT, at least one ART (which may be a multi-component AIT), and a processing unit. The acquired ART formation data can be processed and used to set constraints on the processing of the acquired HFDT formation data. In aspects, a set of processed HFDT data can be used to reinitialize the ART data processing, to allow for a repeated or iterative evaluation process. The system and method generate values used to determine one or more formation properties such as a resistivity of the formation, the presence of an invasion in the formation, mud resistivity or permittivity, anisotropy characteristics of the formation, and dipping characteristics of the formation.

Abstract: Disclosed herein are embodiments of systems, methods, and computer program products for evaluating sand-resistivity and/or sand-conductivity, as well as saturation in laminated shale-sand formations with biaxial anisotropy (BA) in resistivity. In one embodiment, the method determines sand resistivity (Rsd) of the laminated shale-sand formation directly from triaxial resistivities (Rx, Ry, and Rz) of the laminated shale-sand formation based on a bimodal model with BA anisotropy. In another embodiment, the method determines sand resistivity (Rsd) directly based on a bimodal model with transverse isotropy (TI) anisotropy using the triaxial resistivities, horizontal resistivity, and vertical resistivity (Rx, Ry, Rz, Rh, and Rv). In another disclosed embodiment, the above methods may be used to perform quality control on a determined sand-resistivity and saturation of a laminated shale-sand formation.

Abstract: Disclosed herein are embodiments of systems, methods, and computer program products for assessing the data-quality of the calculated reservoir-rock resistivity Rsd in laminar formations. For instance, in one embodiment, a computer-implemented method for assessing the data-quality of the calculated reservoir-rock resistivity Rsd in laminar formations comprises the steps of receiving multi-component induction (MCI) data and other sensor logs data associated with a laminar formation; determining a set of calculated reservoir-rock resistivity Rsd using at least one of the multi-component induction (MCI) data and other sensor logs data; and performing data quality assessments of the set of calculated reservoir-rock resistivity Rsd.

Abstract: In some embodiments, an apparatus and a system, as well as a method and an article, may operate to obtain a plurality of measurements of a formation parameter, each measurement obtained in response to energy propagated into the formation at a plurality of frequencies of propagated energy; to process the measurements over each of the plurality of frequencies to obtain estimated values of the formation parameter; to select an estimated value from the obtained estimated values for each logging depth as a true measurement value for the logging depth based on one or more of the plurality of frequencies and a resistivity range; to generate a combination log that combines a plurality of the true measurement values for each logging depth; and to control a drilling operation based on the combination log. Additional apparatus, systems, and methods are disclosed.

Abstract: A method to minimize borehole effects upon a multi-component induction tool within a well and borehole with water-based mud includes measuring parameters of the reservoir with the induction tool to create an array of measured components. The method further includes comparing a measured component from the array of measured components with a corresponding model component from an array of model components for a reservoir model with known parameters and no borehole effects, and determining the parameters for the reservoir based upon the comparison of the measured component and the corresponding model component.

Abstract: In some embodiments, a multi-array induction method uses user selectable zoning of a borehole to generate an updated look-up table for borehole corrections based on averaged calipers for the borehole. One example method averages caliper data, defines a good zone of the borehole substantially unaffected by corkscrew borehole effect, defines a start depth and an end depth of a zone of the borehole affected by the corkscrew borehole effect, and averages the caliper data for each coil array to generate updated resistivity outputs RO, Rt, and Rf for further drilling of the borehole.

Abstract: In some embodiments, an apparatus and a system, as well as a method and article of manufacture, may operate to parameterize a geological formation in terms of initial earth model parameters, and generate predicted data by simulating a tool response using earth model parameters. Further activity may include determining a difference between calibrated data and the predicted data; and simultaneously adjusting calibration parameters and the earth model parameters such that the difference between them satisfies selected convergence criteria, so that a controlled device can be operated according to at least one of updated calibration parameters, updated calibrated data, or updated earth model parameters. Additional apparatus, systems, and methods are disclosed.

Abstract: A method includes acquiring signals generated from operating a multi-component induction tool in a wellbore. The multi-component induction tool has a plurality of receiver arrays. The method includes generating, for each receiver array at a fixed frequency, a combination of components from the acquired signals, wherein the components corresponds to components of an apparent conductivity tensor. The generating of the combination of components includes generating vertical magnetic dipole (VMD) data and horizontal magnetic dipole (HMD) data. The method includes mixing together the combination of VMD data and HMD data measured from the plurality of receiver arrays and generating data, with respect to evaluation of a formation around the wellbore, from the mixing together of combinations.

Abstract: The disclosure describes enhanced determination of dip and strike/azimuth for real-time MCI data processing in some difficult conditions such as low-dip and low-anisotropy formations using formation properties from surrounding layers. The method is effective for the enhanced determination of dip and azimuth to enhance the inversion accuracy of formation dip and azimuth if the formation anisotropic ratio is low and so reduce the uncertainty of the inverted dip and azimuth.

Abstract: A system and method are described, such as for collecting borehole logging induction data with an induction logging tool. It may then be determined if the borehole logging induction data is within operating limitations of the logging tool. The operating limitations may be defined by a maximum diameter of the borehole at a predetermined mud resistivity. A borehole diameter threshold is determined that is within the operating limitations of the logging tool. When the diameter of the borehole is greater than the borehole diameter threshold, the borehole logging induction data is corrected based on executing an array induction job planner using the borehole diameter threshold at the predetermined mud resistivity.

Abstract: In some embodiments, a multi-array induction method uses user selectable zoning of a borehole to generate an updated look-up table for borehole corrections based on averaged calipers for the borehole. One example method averages caliper data, defines a good zone of the borehole substantially unaffected by corkscrew borehole effect, defines a start depth and an end depth of a zone of the borehole affected by the corkscrew borehole effect, and averages the caliper data for each coil array to generate updated resistivity outputs RO, Rt, and Rf for further drilling of the borehole.

Abstract: In some aspects, systems and methods are provided for determining formation properties using data from both a high-frequency dielectric tool (HFDT) and an array induction tool (AIT). The system includes a controller in communication with at least one HFDT, at least one ART (which may be a multi-component AIT), and a processing unit. The acquired ART formation data can be processed and used to set constraints on the processing of the acquired HFDT formation data. In aspects, a set of processed HFDT data can be used to reinitialize the ART data processing, to allow for a repeated or iterative evaluation process. The system and method generate values used to determine one or more formation properties such as a resistivity of the formation, the presence of an invasion in the formation, mud resistivity or permittivity, anisotropy characteristics of the formation, and dipping characteristics of the formation.

Abstract: In some embodiments, an apparatus and a system, as well as a method and an article, may operate to obtain a plurality of measurements of a formation parameter, each measurement obtained in response to energy propagated into the formation at a plurality of frequencies of propagated energy; to process the measurements over each of the plurality of frequencies to obtain estimated values of the formation parameter; to select an estimated value from the obtained estimated values for each logging depth as a true measurement value for the logging depth based on one or more of the plurality of frequencies and a resistivity range; to generate a combination log that combines a plurality of the true measurement values for each logging depth; and to control a drilling operation based on the combination log. Additional apparatus, systems, and methods are disclosed.

Abstract: Various resistivity logging tools, systems, and methods are disclosed. At least some system embodiments include a logging tool and at least one processor. The logging tool provides transmitter-receiver coupling measurements that include at least direct coupling along the longitudinal tool axis (Czz), direct coupling along the perpendicular axis (Cxx or Cyy), and cross coupling along the longitudinal and perpendicular axes (Cxz, Cyz, Czx, or Czy). The processor performs a multi-step inversion of said transmitter-receiver coupling measurements to obtain values for model parameters. Based at least in part on the model parameters, the processor determines borehole corrections for the transmitter-receiver coupling measurements and may further provide one or more logs derived from the borehole corrected transmitter-receiver coupling measurements.

Abstract: Various embodiments include apparatus and methods to utilize signals acquired from a multi-component induction tool operating in a wellbore. The acquired signals can be correlated to apparent conductivity of a formation and mapped to components of an apparent conductivity tensor. For each receiver array operated by the multi-component induction tool, a combination of these components from the acquired signals can be generated. Combinations generated from different receivers of the multi-component induction tool can be mixed together. From such combinations, data, with respect to evaluation of formation around the wellbore, can be generated. Additional apparatus, systems, and methods are disclosed.

Abstract: The disclosure describes enhanced determination of dip and strike/azimuth for real-time MCI data processing in some difficult conditions such as low-dip and low-anisotropy formations using formation properties from surrounding layers. The method is effective for the enhanced determination of dip and azimuth to enhance the inversion accuracy of formation dip and azimuth if the formation anisotropic ratio is low and so reduce the uncertainty of the inverted dip and azimuth.

Abstract: Various logging tools, systems, and methods are disclosed. An example method includes obtaining multi-component induction (MCI) measurements from a logging tool conveyed along a borehole through a formation. The method also includes comparing a plurality of the MCI measurements to determine one or more data quality indicators for the formation property based at least in part on a predetermined inequality pattern. The method also includes displaying the one or more data quality indicators.

Abstract: Apparatus and techniques are described, such as for obtaining information indicative of a formation resistivity near a casing, such as using an array laterolog apparatus. For example, raw measurements received from a well tool in a borehole near a casing may indicate a resistivity of a geologic formation through which the borehole extends. Any errors or interference in the raw measurements caused by the proximity of the well tool to the casing may be removed to eliminate the casing effect on the raw measurements. In some examples, a signal and formation libraries that include casing specific parameters may be used in conjunction with non-casing optimized signal and formation libraries to perform correction mapping of raw measurements. The corrections and their application to the raw measurements may be based on the position of a well logging tool with respect to a casing termination point.

Abstract: Various resistivity logging tools, systems, and methods are disclosed. At least some system embodiments include a logging tool and at least one processor. The logging tool provides transmitter-receiver coupling measurements that include at least direct coupling along the longitudinal tool axis (Czz), direct coupling along the perpendicular axis (Cxx or Cyy), and cross coupling along the longitudinal and perpendicular axes (Cxz, Cyz, Czx, or Czy). The processor performs a multi-step inversion of said transmitter-receiver coupling measurements to obtain values for model parameters. Based at least in part on the model parameters, the processor determines borehole corrections for the transmitter-receiver coupling measurements and may further provide one or more logs derived from the borehole corrected transmitter-receiver coupling measurements.