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Measurements of Fine Volcanic ASH Via Stereoscopy in the Scanning Electron Microscope

Published online by Cambridge University Press:  02 July 2020

O.P. Mills ,
W.I. Rose  and
C.M. Riley
O.P. Mills
Affiliation:
Department of Metallurgical and Materials Engineering, Michigan Technological University, Houghton, MI, 49930
W.I. Rose
Affiliation:
Geological Engineering and Sciences, Michigan Technological University, Houghton, MI, 49930
C.M. Riley
Affiliation:
Geological Engineering and Sciences, Michigan Technological University, Houghton, MI, 49930
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Extract

Volcanic eruptions inject tons of silicic material into the atmosphere. Large, dense material falls out within a few hours whereas fine size fractions, < 10 μm radius ash, may remain airborne for weeks to months. Protection of human population centers and aircraft requires predictive atmospheric transport models. Many of these models assume the ash particles are spherical but abundant qualitative studies of ash particles demonstrate irregular shapes ranging from parachute-like bubble-wall shards to polygonal shaped mineral grains. These non-spherical shapes increase atmospheric drag. The accuracy of transport models may be improved with a better understanding of the actual shapes found in fine ash particles. Therefore, the objective of this study is to accurately determine three-dimensional shape measurements via stereoscopic methods using the scanning electron microscope.

The scanning electron microscope is an ideal imaging platform for collection of stereo pairs because of its utility in stereoscopic height measurement.

Type
Microscopy and Microanalysis in the “Real World”
Information
Microscopy and Microanalysis , Volume 4 , Issue S2: Proceedings: Microscopy & Microanalysis '98, Microscopy Society of America 56th Annual Meeting, Microbeam Analysis Society 32nd Annual Meeting, Atlanta, Georgia July 12-16, 1998 , July 1998 , pp. 502 - 503
Copyright
Copyright © Microscopy Society of America

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References

1 Chuan, R.L. et al., SEM Characterization of Small Particles in Eruption Clouds, in Clastic Particles, ed. Marshall, J.R., Reinhold, van Nostrand, New York, (1987)159.Google Scholar

2 Wilson, L. and Huang, T.C., The Influence of Shape on the Atmospheric Settling Velocity of Volcanic Ash Particles, Earth and Planetary Science Letters, 44(1979)311.CrossRefGoogle Scholar

3 Howell, P.G.T. and Boyde, A., Comparison of Various Methods for Reducing Measurements from Stereo-Pair Scanning Electron Micrographs to “Real 3-D Data”, Scanning Electron Micrscopy/1972, Proc. Fifth Annual SEM Symposium, (1972)233.Google Scholar

4 Riley, C.M et al., Shape Analysis of Airfall Particles in Anomalously Thick Distal Airfall Deposits and Secondary Maxima, Fall AGU Conference, (1997).Google Scholar

5 This research is supported in part by the Michigan Space Grant Consortium.Google Scholar