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Published on: February 3, 2018
Quantitative mapping of geological samples by electron microprobe using mean atomic number (MAN) background
1Department of Geology, William & Mary, McGlothlin-Street Hall rm 228, 251 Jamestown Rd, Williamsburg, VA 23185, USA.
Methodsx
|May 21, 2026
Summary
This study introduces a new method for chemical analysis of geological samples using electron probe microanalysis (EPMA) mapping. This approach combines quantitative accuracy with high spatial resolution for detailed mineral composition analysis.
Area of Science:
- Geochemistry
- Mineralogy
- Analytical Chemistry
Background:
- Electron probe microanalysis (EPMA) and wavelength dispersive spectroscopy (WDS) are standard for geological sample analysis.
- Current methods are limited to either spatially-limited quantitative spot analysis or qualitative mapping.
- A need exists for methods combining quantitative accuracy with spatial resolution.
Purpose of the Study:
- To present a novel method integrating quantitative spot analysis with EPMA mapping.
- To enable detailed characterization of mineral composition and variations in geological samples.
- To facilitate texturally-informed thermobarometric calculations.
Main Methods:
- Utilizing the mean atomic number (MAN) background-correction routine for EPMA mapping.
- Implementing data filtering workflows based on mineralogical identification and stoichiometry.
- Employing free and open-source geographic information systems (GIS) software for data visualization.
Main Results:
- Efficient and accurate quantitative chemical maps of geological samples were produced.
- Meaningful mineral composition data was obtained through data filtering.
- GIS software enabled effective exploration of multi-dimensional quantitative EPMA map data.
Conclusions:
- The developed method successfully combines quantitative analysis with spatial resolution in EPMA.
- This approach enhances the systematic characterization of geological sample compositions and textures.
- The method offers broader applications in geological research, including thermobarometry.
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