High resolution 3D confocal microscope imaging of volcanic ash particles

David Wertheim; Gavin Gillmore; Ian Gill; Nick Petford

doi:10.1016/j.scitotenv.2017.02.230

High resolution 3D confocal microscope imaging of volcanic ash particles

Sci Total Environ. 2017 Jul 15:590-591:838-842. doi: 10.1016/j.scitotenv.2017.02.230. Epub 2017 Mar 9.

Authors

David Wertheim¹, Gavin Gillmore², Ian Gill², Nick Petford³

Affiliations

¹ Faculty of Science, Engineering and Computing, Kingston University, Surrey, UK. Electronic address: D.Wertheim@kingston.ac.uk.
² Faculty of Science, Engineering and Computing, Kingston University, Surrey, UK.
³ University of Northampton, Northampton, UK.

PMID: 28284651
DOI: 10.1016/j.scitotenv.2017.02.230

Abstract

We present initial results from a novel high resolution confocal microscopy study of the 3D surface structure of volcanic ash particles from two recent explosive basaltic eruptions, Eyjafjallajökull (2010) and Grimsvötn (2011), in Iceland. The majority of particles imaged are less than 100μm in size and include PM₁₀s, known to be harmful to humans if inhaled. Previous studies have mainly used 2D microscopy to examine volcanic particles. The aim of this study was to test the potential of 3D laser scanning confocal microscopy as a reliable analysis tool for these materials and if so to what degree high resolution surface and volume data could be obtained that would further aid in their classification. First results obtained using an Olympus LEXT scanning confocal microscope with a ×50 and ×100 objective lens are highly encouraging. They reveal a range of discrete particle types characterised by sharp or concave edges consistent with explosive formation and sudden rupture of magma. Initial surface area/volume ratios are given that may prove useful in subsequent modelling of damage to aircraft engines and human tissue where inhalation has occurred.

Keywords: Confocal; Microscopy; Volcanic ash particles.