Explosive to effusive transition during the largest volcanic eruption of the 20th century (Novarupta 1912, Alaska)

  title={Explosive to effusive transition during the largest volcanic eruption of the 20th century (Novarupta 1912, Alaska)},
  author={C. T. Nguyen and Helge M. Gonnermann and Bruce F. Houghton},
Silicic volcanic eruptions commonly show abrupt shifts between powerful and dangerous (Plinian) explosive episodes and gentle effusion of lava. Whether the onset of magma permeability and ensuing gas loss controls these transitions has been a subject of debate. We measured porosities and permeabilities in samples from the A.D. 1912 eruption of Novarupta volcano, Alaska, and analyzed them within the context of a well-constrained eruptive sequence that encompasses sustained explosive and effusive… 

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    Geological Society, London, Special Publications
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