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Quantitative Magnetic Resonance Imaging of Skeletal Muscle Disease
Published on: December 18, 2016
Inverting MRI measurements to heterogeneity spectra
Andrew E Pomerantz1, Peter Tilke, Yi-Qiao Song
1Reservoir Geosciences, Schlumberger-Doll Research, 1 Hampshire Street, Cambridge, MA 02139, USA. apomerantz@slb.com
Journal of Magnetic Resonance (San Diego, Calif. : 1997)
|June 14, 2008
Summary
This study uses magnetic resonance imaging (MRI) to quantify spatial heterogeneity in rock cores. A novel geostatistical method reveals detailed heterogeneity spectra, improving porous media characterization.
Area of Science:
- Geophysics
- Petrophysics
- Materials Science
Background:
- Assessing spatial heterogeneity in porous rocks is crucial for understanding fluid flow and reservoir properties.
- Traditional geostatistical methods like variograms can be ambiguous in quantifying heterogeneity.
- Magnetic Resonance Imaging (MRI) offers a non-destructive method for probing rock interiors.
Purpose of the Study:
- To develop and apply a geostatistical technique to resolve ambiguities in quantifying spatial heterogeneity in sandstone and carbonate rock cores.
- To investigate the influence of regularization (spatial averaging) on variogram analysis.
- To derive a heterogeneity spectrum from MRI data for a more detailed characterization of porous media.
Main Methods:
- Spatially resolved magnetic resonance imaging (MRI) measurements of porosity and relaxation time.
- Application of geostatistical techniques, including experimental variograms.
- Modeling the effect of regularization on variograms to enable inversion.
- Calculation of heterogeneity spectra as a function of length scale.
Main Results:
- The study successfully modeled the influence of regularization on variograms, allowing for inversion into heterogeneity spectra.
- Heterogeneity spectra revealed significant variations in spatial heterogeneity across different carbonate samples within the 0.3-100mm length scale.
- The derived heterogeneity spectra provide a more detailed description of porous media compared to standard variograms or porosity distribution moments.
Conclusions:
- The developed MRI-based geostatistical approach effectively quantifies spatial heterogeneity in rock cores.
- This method provides a more nuanced understanding of porous media structure by analyzing heterogeneity across multiple length scales.
- The findings highlight the significant variability of spatial heterogeneity in carbonate rocks, underscoring the need for advanced characterization techniques.
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