G01V3/24

Method for resistivity determination with borehole imagers

A method and system for resistivity imaging. A method may comprise disposing a downhole tool into a borehole, applying a voltage difference between the array of injector electrodes, constructing a first set of formation images for each of the plurality of frequencies, applying a mud effect removal algorithm to produce a second set of formation images for each of the plurality of frequencies, applying a dielectric correction algorithm to each of the plurality of frequencies to produce a third set of formation images for each of the plurality of frequencies, and combining the first set of formation images, the second set of formation images, and the third set of formation images to obtain a blended image. A system for resistivity imaging may comprise a downhole tool. The downhole tool may comprises a pad, an array of injector electrodes, and one or more return electrodes.

Method for resistivity determination with borehole imagers

A method and system for resistivity imaging. A method may comprise disposing a downhole tool into a borehole, applying a voltage difference between the array of injector electrodes, constructing a first set of formation images for each of the plurality of frequencies, applying a mud effect removal algorithm to produce a second set of formation images for each of the plurality of frequencies, applying a dielectric correction algorithm to each of the plurality of frequencies to produce a third set of formation images for each of the plurality of frequencies, and combining the first set of formation images, the second set of formation images, and the third set of formation images to obtain a blended image. A system for resistivity imaging may comprise a downhole tool. The downhole tool may comprises a pad, an array of injector electrodes, and one or more return electrodes.

Electromagnetic imager design

A method for identifying an operating frequency may comprise performing a frequency sweep using one or more injector electrodes disposed on a downhole tool, recording one or more measurements from the frequency sweep, identifying one or more stable frequencies from the frequency sweep, and identifying one or more operating frequencies from the one or more stable frequencies. A system for electrical isolation may comprise a downhole tool, a pad, an arm, wherein the arm is attached to the mounting bracket and the mandrel, and an information handling system connected to the pad through the first set of electronics and the second set of electronics. The downhole tool may comprise a mandrel, a chassis disposed in the mandrel, and a first set of electronics disposed in the chassis.

Dual range micro-resistivity measurement method

A resistivity imaging device and a method of operating the resistivity imaging device in a wellbore. The resistivity imaging device includes a first electrode, a second electrode, and a circuit electrically coupled to the first electrode and the second electrode. An impedance is measured of a formation surrounding the wellbore. Based on the impedance, the circuit is configured into one of a first circuit configuration for operating the resistivity imaging device in a first mode and a second circuit configuration for operating the resistivity imaging device in a second mode. The resistivity imaging device is operated using the circuit in the one of the first circuit configuration and the second circuit configuration.

Dual range micro-resistivity measurement method

A resistivity imaging device and a method of operating the resistivity imaging device in a wellbore. The resistivity imaging device includes a first electrode, a second electrode, and a circuit electrically coupled to the first electrode and the second electrode. An impedance is measured of a formation surrounding the wellbore. Based on the impedance, the circuit is configured into one of a first circuit configuration for operating the resistivity imaging device in a first mode and a second circuit configuration for operating the resistivity imaging device in a second mode. The resistivity imaging device is operated using the circuit in the one of the first circuit configuration and the second circuit configuration.

Systems And Methods For Production And Reservoir Monitoring
20230133939 · 2023-05-04 · ·

A system and method for identifying a downhole fluid. The system may include at least one electrode station that is disposed on a non-conductive material and at least two electrodes coupled to the at least one electrode station. The system may further include at least one acquisition unit that is configured to measure a voltage across the two electrodes of the at least one electrode station and an information handling system connected to the at least one acquisition unit. The method may include injecting a current into a sensing domain with at least two electrodes disposed on at least one electrode station, measuring a voltage across the at least two electrodes at the at least one electrode station using an acquisition unit, and sending the measured voltage to an information handling system connected to the acquisition unit by at least one communication line.

INSTRUMENT STRUCTURE AND MEASURING METHOD FOR CROSS-CASING RESISTIVITY TOOL
20230341580 · 2023-10-26 ·

The present application provides a device and method for determining formation resistivity outside casing. The device measures the electrical signal of alternating current flowing along the casing, and then calculates phase velocity, group velocity, time difference, amplitude attenuation, and phase difference of the alternating current along the casing. Using these relationships between phase velocity, group velocity, time differences, amplitude attenuation, and phase difference, the formation resistivity outside the casing is calculated.

INSTRUMENT STRUCTURE AND MEASURING METHOD FOR CROSS-CASING RESISTIVITY TOOL
20230341580 · 2023-10-26 ·

The present application provides a device and method for determining formation resistivity outside casing. The device measures the electrical signal of alternating current flowing along the casing, and then calculates phase velocity, group velocity, time difference, amplitude attenuation, and phase difference of the alternating current along the casing. Using these relationships between phase velocity, group velocity, time differences, amplitude attenuation, and phase difference, the formation resistivity outside the casing is calculated.

Dip detection in logging image processing

A method for imaging a downhole formation. The method includes combining the captured images to generate a partial image of the formation, wherein the partial image includes captured images separated by gaps representing portions of the formation not captured with sensors what were disposed downhole. The method includes locating dips in the formation within the partial image and interpolating the partial image using the located dips within the partial image.

Ranging and resistivity evaluation using current signals

Methods, systems, and computer program products use current leakage rates to evaluate the resistivity of a subterranean formation around a drilling well in conjunction with a ranging operation. The evaluation entails obtaining a current distribution along a section of the drilling well as part of a ranging measurement. The current distribution allows the current leakage rate to be determined along that section of the drilling well. Multiple current leakage rates may then be determined along the drilling well to produce a leakage rate curve that may be matched with modeled or known leakage rate curves to estimate the formation resistivity around the drilling well. Formation resistivity may also be calculated from the current distribution using an appropriate equation. The ability to obtain a current distribution along a section of the drilling well as part of a ranging measurement allows formation resistivity to be evaluated in conjunction with ranging operations.