Tephra from ice- A simple method to routinely mount, polish, and quantitatively analyze sparse fine particles.

Area of Science:

• Geoscience
• Materials Science
• Analytical Chemistry

Background:

• Studying fine particles like volcanic ash (tephra) and atmospheric dust in glacial ice requires specialized mounting and analysis techniques.
• Existing methods can be complex and may not preserve particle integrity or position for subsequent analyses.

Purpose of the Study:

• To develop a versatile graphite substrate method for mounting and analyzing sparse, fine particles from liquid suspensions.
• To enable improved, multi-method analysis of volcanic ash and atmospheric dust preserved in glacial ice.

Main Methods:

• A novel method utilizing a graphite substrate for mounting fine particles from liquid suspensions.
• Scanning electron microscope-energy dispersive spectrometry (SEM-EDS) at full vacuum without conductive coating for unpolished grains.
• Subsequent polishing and analysis of the same grains using SEM-EDS, electron probe microanalysis, laser ablation-inductively coupled plasma-mass spectroscopy, secondary ion mass spectrometry, and optical microscopy.

Main Results:

• Successfully prepared and analyzed particles as small as 3-5 micrometers.
• Enabled analysis of unpolished grains directly on the graphite substrate.
• Facilitated multi-technique analysis of the same particles in the same positions after polishing.

Conclusions:

• The graphite substrate method offers a flexible and efficient approach for preparing and analyzing fine particles from glacial ice.
• This technique enhances the study of volcanic ash and atmospheric dust by allowing for detailed, multi-modal characterization.
• The method is adaptable for various sample types and analytical techniques, improving accessibility for researchers.