Microstrip Antenna Logging Tool for Borehole Dielectric Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing logging tools face limitations in robustness and accuracy, particularly in hostile drilling environments and in measuring dielectric properties of downhole formations effectively.
Innovation Solution
The use of microstrip antenna-based logging tools and systems that integrate microstrip antennas into drilling assemblies and wireline logging tools, enabling the measurement of scattering coefficients to derive formation properties like permittivity and resistivity, with advanced signal processing and modeling techniques to enhance accuracy and robustness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional logging tools are used in hostile drilling environments, then mechanical support and electrical connection are provided, but robustness and measurement accuracy deteriorate
Solution Approach 1:
The patent replaces traditional mechanical and electrical logging tools with microstrip antenna-based electromagnetic measurement systems. The microstrip antennas transmit and receive electromagnetic signals through the borehole wall to measure formation dielectric properties, eliminating the need for direct mechanical contact and electrical connections with the formation, thereby improving both robustness in hostile environments and measurement accuracy
Solution Approach 2:
The patent changes the measurement parameter from direct electrical conductivity measurements to dielectric constant measurements using microstrip antennas. By measuring the complex propagation constant of electromagnetic waves at multiple frequencies, the system derives formation properties including water-filled porosity and water saturation, achieving accurate measurements in environments where traditional electrical tools fail
2Measurement precision
If dielectric logging tools are used to measure formation properties, then water-filled porosity and water saturation can be determined, but existing tool designs have limitations on robustness and accuracy
Solution Approach 1:
The patent employs microstrip antennas that can dynamically adjust their operating characteristics through electronic control of the signal source frequency and power. The system measures scattering coefficients at multiple frequencies and uses coherent detection to dynamically process signals, enabling adaptive measurement conditions that improve both accuracy and robustness across varying formation properties and borehole conditions
Solution Approach 2:
The patent uses microstrip antennas as intermediaries that couple electromagnetic energy between the logging tool and the formation through the borehole wall and drilling fluid. This indirect coupling method allows measurement of formation dielectric properties without direct contact, protecting the tool from hostile downhole conditions while maintaining measurement accuracy through sophisticated signal processing of the scattered electromagnetic waves
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
These tools provide robust and accurate measurements of dielectric properties, enabling effective characterization of downhole formations, including hydrocarbon saturation and porosity, with improved spatial resolution and depth of investigation.
Implementation Method 1
one or more microstrip antennas disposed on a wall-contacting face of the logging tool. The one or more microstrip antennas include a transmit antenna
Implementation Method 2
a coherent receiver to measure one or more scattering coefficients
Data Source
AI summary
A dielectric logging tool for use in a borehole that penetrates a subsurface formation, includes: at least one wall-contacting face with one or more embedded microstrip antennas including a transmit antenna; an oscillator that supplies a transmit signal; a coherent receiver that measures the one or more scattering coefficients; and a processor that derives a formation property from the one or more scattering coefficients. The tool may be conveyed along a borehole, with the scattering coefficients and derived formation property values associated with tool position and orientation to provide a permittivity log.