DETECTION OF LOW RESISTIVITY PAY ZONES USING SPECTRAL INDUCED POLARIZATION METHOD

CIRCUIT AND APPARATUS FOR GENERATING SIGNAL SOURCE FOR IMPEDANCE MEASUREMENT OF ROCK AND ORE SAMPLES

ELECTROMAGNETIC MEASUREMENTS IN A CURVED WELLBORE

Instrument structure and measuring method for cross-casing resistivity tool

Apparatus and method for measuring thickness of tubings in downhole applications

Dual range micro-resistivity measurement method

Resistivity imaging system with compensator for parasitic impedances between electrodes and their conductive substrates

System and method for characterizing subterranean formations

Method for resistivity determination with borehole imagers

Well logging tool and interpretation framework that employs a system of artificial neural networks for quantifying mud and formation electromagnetic properties

Process and system for enhanced depth penetration of an energy source

Using electrical signal as a measure of water wettability for direct emulsion fluids

Method for resistivity determination with borehole imagers

Method to estimate formation resistivity

Current injection via capacitive coupling

Calculation of mud angle for imaging wells with oil based muds

System and methodology of cross casing resistivity tool

Process and system for enhanced depth penetration of an energy source

High Voltage Protection and Receiver Saturation Prevention Apparatus with High Voltage Peeking Functions for Downhole Logging

Electronics assemblies for downhole use

High Frequency Or Multifrequency Resistivity Tool

Processing resistivity images in wells with oil based muds

Breaker fluids and methods of use thereof

Apparatus and downhole tools for measuring hydrogen sulfide in downhole fluids

Device for determining petrophysical parameters of an underground formation

Monitoring hydrocarbon reservoirs using induced polarization effect

Method of detecting substance saturation in a formation

Radio test system and method for testing a device under test

Process and system for enhanced depth penetration of an energy source

Monitoring hydrocarbon reservoirs using induced polarization effect

Determining standoff between a wall of a wellbore and a tool disposed in the wellbore

Determining borehole parameters using ultrasonic and micro-resistivity calipers

Ranging and resistivity evaluation using current signals

Determining subterranean-formation resistivity using an electromagnetic telemetry system

Downhole apparatus and technique to measure fluid resistivity

Skin effect correction for focused electrode devices based on analytical model

DIGITAL EXCITATION SIGNAL GENERATOR FOR DOWNHOLE LOGGING TOOLS

Dual-guard imager probe

Methods and apparatus for performing a well survey

Electrode-based tool measurement corrections based on measured leakage currents

Formation resistivity measurement apparatus, systems, and methods

Method and apparatus for determining resistivity of a formation

Downhole electromagnetic communications between two wells

Methods of logging

Breaker fluids and methods of use thereof

Measurement while drilling system and method

Method and system for formation texture and rock type identification

Real-time downhole processing and detection of bed boundary

Fluid characterization apparatus, systems, and methods

Impedance analysis for fluid discrimination and monitoring

Laterolog array tool for performing galvanic measurement

Correcting for monitoring electrodes current leakage in galvanic tools

Methods and systems for obtaining an electrical impedivity and/or resistivity image of a subterranean formation

Method and apparatus for determining a fracture aperture in a wellbore

GENERATOR FOR LATEROLOG TOOL

Resistivity measurement using a galvanic tool

Plastic frack tracer

Wear resistant electrodes for downhole imaging

Monitoring hydrocarbon reservoirs using induced polarization effect

Apparatus, methods and systems for downhole testing of electronic equipment

Hybrid image of earth formation based on transient electromagnetc measurements

Methods to characterize formation properties

Resistivity logging tool with excitation current control based on multi-cycle comparison

Method of determining CEC and other properties from multi-frequency dielectric measurements

Crosstalk suppression or removal for galvanic measurements

Capacitivity and frequency effect index detection device and method, and explorative substance identification method

Methods of and apparatuses for identifying geological characteristics in boreholes

Methods of and apparatuses for identifying geological characteristics in boreholes

Carbonaceous nanoparticles as conductivity enhancement additives to water-in-oil emulsions, oil-in-water emulsions and oil-based wellbore fluids

Method and system for calibrating a downhole imaging tool

Dual mode balancing in OBM resistivity imaging

System and method to induce an electromagnetic field within the earth

Proximity detection system for deep wells

Tool for imaging a downhole environment

System and method of focusing an array laterolog

Mapping hydrocarbon liquid properties of a kerogencontaining source rock

Focused array laterolog tool

Detecting bed boundary locations based on gradients determined from measurements from multiple tool depths in a wellbore

Borehole electric field survey with improved discrimination of subsurface features

Methods and systems for obtaining an electrical impedivity and/or resistivity image of a subterranean formation

Multi-array laterolog tools and methods with split monitor electrodes

Borehole log data processing methods

Fast inversion of MWD transient EM data excited by a pulse of an arbitrary shape

Methods of and apparatuses for identifying geological characteristics in boreholes

System and method for imaging properties of subterranean formations

Intelligent spectral induced polarization measurement module

Systems and methods for investigating a formation surrounding a borehole

Phase-based electromagnetic surveys for geological formations

Apparatus and method for balancing impedance of a resistivity measuring tool

Systems and methods for resistivity measurement at multiple angles of rotation

System and method for generating fluid compensated downhole parameters

Apparatus and method for measuring electrical properties of an underground formation

System and method for measuring downhole parameters

Multi-array laterolog tools and methods

Multi-array laterolog tools and methods with differential voltage measurements

Method for real-time downhole processing and detection of bed boundary for geosteering application

Fluid resistivity sensor

Systems and methods for the determination of formation water resistivity and conductivity

Borehole resistivity imager using discrete energy pulsing

Pore parameters and hydraulic parameters from electric impedance spectra

Connection method of replaceable sensors for resistivity arrays

Proximity detection system for deep wells

Drill bit assembly having electrically isolated gap joint for measurement of reservoir properties

WELLBORE LOGGING PERFORMANCE VERIFICATION METHOD AND APPARATUS

Apparatus and method for formation resistivity measurements in oil-based mud using a floating reference signal

Formation resistivity measurements using phase controlled currents

CNT FIBER BASED IMPEDANCE SPECTROSCOPY FOR CHARACTERIZING DOWNHOLE FLUIDS

Apparatus and method for actively balancing impedance of a resistivity measuring tool

Systems and methods for investigating a formation surrounding a borehole

Imaging in oil-based mud by synchronizing phases of currents injected into a formation

HIGH-POWER ELECTROMAGNETIC PULSE LAUNCHER IN WELL

Concentric buttons of different sizes for imaging and standoff correction

Method of manufacture and the use of a functional proppant for determination of subterranean fracture geometries

System and method for imaging properties of subterranean formations

Method of correcting resistivity measurements for toll bending effects

Apparatus and method for capacitive measuring of sensor standoff in boreholes filled with oil based drilling fluid

Multiple depths of investigation using two transmitters

Active standoff compensation in measurements with oil-based mud resistivity imaging devices

Resistivity imaging using phase sensitive detection with a floating reference signal

Method for determining spatial distribution of fluid injected into subsurface rock formations

Oil-based mud imager with a line source

CURRENT MEASUREMENT FOR WATER-BASED MUD GALVANIC ELECTRICAL IMAGING AND LATEROLOG TOOLS

Tool for imaging a downhole environment

Tool for imaging a downhole environment

Method for mitigating leakage currents

Method and apparatus with high resolution electrode configuration for imaging in oil-based muds

Tool for imaging a downhole environment

Tool for imaging a downhole environment

Logging tool employing a monopole current injection electrode for microresistivity imaging

Calibration method for a microresistivity logging tool

Microresistivity anisotropy logging tool employing a monopole current injection electrode

Concentric return and transmitter electrodes for imaging and standoff distances compensation

Apparatus and method for balancing impedance of a resistivity measuring tool

Sensor for determining downhole parameters and methods for using same

Microresistivity imaging in conductive and nonconductive drilling fluid

Microresistivity imaging at multiple depths of investigation

Wellbore logging performance verification method and apparatus

Method and apparatus for galvanic multi-frequency formation resistivity imaging

METHODS AND APPARATUS FOR PROVIDING COMPLIMENTARY RESISTIVITY AND STANDOFF IMAGE

Oil based mud imaging tool with common mode voltage compensation

Drilling systems and methods using radial current flow for boundary detection or boundary distance estimation

Method for determination of the oil formation's water-flooding area radius in the wellbore zone

Proximity detection system for deep wells

Wireline communication system for deep wells

High resolution voltage sensing array

High Frequency or Multifrequency Resistivity Tool

Method for electrical investigation of a borehole

System and method for measuring resistivity parameters of an earth formation

Multi-resolution borehole resistivity imaging

Concentric buttons of different sizes for imaging and standoff correction

Multi-resolution borehole resistivity imaging

Tool for electrical investigation of a borehole

Methods and apparatus for determining a presence of a non-conductive coating on electrodes in downhole fluid resistivity measurement devices

Analog front-end coherent in-phase demodulation data acquisition system for resistivity image tools

Coherent in-phase demodulation for resistivity image tools with spread spectrum continuous phase modulation stimulus

Sequential resistivity imaging with asymmetric electrode arrays

Displaced electrode amplifier

Apparatus for formation resistivity imaging in wells with oil-based drilling fluids

Apparatus for Formation Resistivity Imaging in Wells with Oil-Based Drilling Fluids

Statistical correction for standoff in two-terminal imager operating in oil-based mud

Method of manufacture and the use of a functional proppant for determination of subterranean fracture geometries

Apparatus and method for imaging subsurface materials using a pad having a plurality of electrode sets

Correction of sensor non-equipotentiality in a resistivity imaging device

Wellbore logging performance verification method and apparatus

Resistivity imaging using phase sensitive detection with a floating reference signal

Method and system of calculating resistivity of an earth formation

Method and apparatus for resistivity measurements using dual impedance voltage measurements

SINGLE-DIPOLE HIGH FREQUENCY ELECTRIC IMAGER

Applications of wideband EM measurements for determining reservoir formation properties

Logging while drilling tool for obtaining azimuthally sensitive formation resistivity measurements

Two-axial pad formation resistivity imager

Permittivity measurements with oil-based mud imaging tool

Multiple frequency based leakage correction for imaging in oil based muds

Multi-frequency cancellation of dielectric effect

Downhole multi-phase flow imager

Correction of sensor non-equipotentiality in a resistivity imaging device

Method and apparatus for combined induction and imaging well logging

Method and apparatus for resistivity imaging in boreholes with an antenna and two spaced apart electrodes

Mixed galvanic-inductive imaging in boreholes

Oil-based mud resistivity imaging using resonant circuits

Apparatus and method for resistivity measurements during rotational drilling

Method and apparatus for measuring formation conductivities from within cased wellbores by combined measurement of casing current leakage and electromagnetic response

Two-axial pad formation resistivity imager

Oil based mud imaging tool with common mode voltage compensation

Standoff compensation for imaging in oil-based muds

Method for compensating dielectric attenuation in downhole galvanic measurements

Method and apparatus for borehole wall resistivity imaging in the presence of conductive mud and rugose borehole

High resolution resistivity earth imager

Method and apparatus for enhancing formation resistivity images obtained with downhole galvanic tools

High resolution resistivity earth imager

Reflection coefficient measurement for water-based mud resistivity imaging

High resolution resistivity earth imager

Highly integrated logging tool

Shielded apparatus for reducing an electrical field generated by a pad during electrically exploring geological formations

Method and system for calculating resistivity of an earth formation

Shoulder bed effects removal

Well logging apparatus for obtaining azimuthally sensitive formation resistivity measurements

Non-invasive measurement of fluid-pressure diffusivity using electro-osmosis

Method for compensating dielectric attenuation in downhole galvanic measurements

Method and apparatus for measuring formation conductivities from within cased wellbores by combined measurement of casing current leakage and electromagnetic response

System for measuring Earth formation resistivity through an electrically conductive wellbore casing

System for measuring earth formation resistivity through and electrically conductive wellbore casing

Method for measuring earth formation resistivity through an electrically conductive wellbore casing

Method and a tool for electrically investigating a wall of a borehole in a geologic formation

Multi-mode oil base mud imager

Apparatus and methods for measuring formation characteristics in presence of conductive and non-conductive muds

Apparatus and methods for imaging wells drilled with oil-based muds

Apparatus and method for resistivity measurements during rotational drilling

Dynamic diameter measurement device for downhole wireline cables

Multi-frequency electrical impedance tomography

Subsurface data transfer using well fluids