Quantitative models of the fallout and dispersal of tephra from volcanic eruption columns

  title={Quantitative models of the fallout and dispersal of tephra from volcanic eruption columns},
  author={Sn Carey and R. Stephen J. Sparks},
  journal={Bulletin of Volcanology},
A theoretical model of clast fallout from convective eruption columns has been developed which quantifies how the maximum clast size dispersal is determined by column height and wind strength. An eruption column consists of a buoyant convecting region which rises to a heightHB where the column density equals that of the atmosphere. AboveHB the column rises further to a heightHT due to excess momentum. BetweenHT andHB the column is forced laterally into the atmosphere to form an upper umbrella… 
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