eEarth Discussions www.electronic-earth-discuss.net 1815-3836 1815-3844 2 4 2007 10.5194/eed-2-151-2007 http://www.electronic-earth-discuss.net/2/151/2007/ http://www.electronic-earth-discuss.net/2/151/2007/eed-2-151-2007.html http://www.electronic-earth-discuss.net/2/151/2007/eed-2-151-2007.pdf 151 167 2007-11-05 Impact vesiculation – a new trigger for volcanic bubble growth and degassing D. A. Rothery d.a.rothery@open.ac.uk J. M. Sumner O. Spieler D. B. Dingwell Department of Earth Sciences, Open University, Milton Keynes, MK7 6AA, UK Institut für Mineralogie, Petrologie und Geochemie, Ludwig-Maximilians-Universität, Theresienstrasse 41/III, 80333 München, Germany We highlight a potentially important trigger for bubble growth and degassing in volcanic bombs. We have successfully triggered bubble growth in previously unvesiculated samples of silicate melt during experiments to simulate volcanic bomb impact, by firing pellets at, and dropping weights onto, melt samples. 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