Borehole Imaging Binning via Mathematical Fitting Functions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional borehole imaging techniques during logging while drilling (LWD) face challenges due to limited communication bandwidth and data storage capacity, resulting in coarse or grainy images, especially when using a small number of azimuthal sectors, which distorts high-frequency components and introduces aliasing, while using a large number of sectors may not provide enough data points for stable output.
Innovation Solution
The method involves acquiring logging sensor measurements and corresponding azimuth angles during LWD, fitting data pairs within azimuthal windows with mathematical functions (such as polynomials), and evaluating these functions at specific positions to generate sector values, allowing for more accurate representation of data, especially when data is non-linearly distributed or when few measurements are available in a sector, thereby improving image quality and reducing noise.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If conventional binning is used with a small number of azimuthal sectors, then data reduction is achieved, but image quality deteriorates and aliasing occurs
Solution Approach 1:
The patent applies windowing functions (mathematical transformations) to the sensor data before binning, changing the parameter domain from raw measurements to transformed measurements. This transformation allows the data to be binned more effectively while preserving high-frequency components and reducing aliasing, thus maintaining image quality while achieving data reduction
Solution Approach 2:
The patent performs windowing transformation on the sensor data before the binning operation. This preliminary action prepares the data in a form that is more suitable for binning, allowing subsequent binning to produce higher quality images with less aliasing compared to direct binning of raw data
2Manufacturing precision
If conventional binning is used with a large number of azimuthal sectors, then image quality is improved, but data storage requirements increase
Solution Approach 1:
By applying windowing functions to transform the data parameters, the patent enables more efficient binning that achieves better image quality with fewer bins. The transformation concentrates the information in a way that reduces the total number of bins needed while maintaining or improving image quality
3Manufacturing precision
If windowing techniques are applied, then image resolution and noise rejection are improved, but computational complexity increases
Solution Approach 1:
The windowing function is applied as a preliminary transformation to each sensor measurement before binning. This pre-processing step, while adding computational complexity, enables subsequent binning operations to be more efficient and produce higher quality images with better noise rejection
Data Source
AI summary
A method for forming a borehole image includes fitting logging sensor measurements residing in each of a plurality of azimuthal windows with corresponding mathematical fitting functions. The functions may then be evaluated at one or more corresponding azimuthal positions to obtain at least one sector value for each of the azimuthal windows. A two dimensional borehole image may be formed by repeating the procedure at multiple measured depths in the borehole.