Formation of high-grade ignimbrites Part II. A pyroclastic suspension current model with implications also for low-grade ignimbrites

  title={Formation of high-grade ignimbrites Part II. A pyroclastic suspension current model with implications also for low-grade ignimbrites},
  author={Armin Freundt},
  journal={Bulletin of Volcanology},
  • A. Freundt
  • Published 12 April 1999
  • Geology
  • Bulletin of Volcanology
Abstract Analogue experiments in part I led to the conclusion that pyroclastic flows depositing very high-grade ignimbrite move as dilute suspension currents. In the thermo–fluid–dynamical model developed, the degree of cooling of expanded turbulent pyroclastic flows dynamically evolves in response to entrainment of air and mass loss to sedimentation. Initial conditions of the currents are derived from column-collapse modeling for magmas with an initial H2O content of 1–3 wt.% erupting through… 
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  • A. Freundt
  • Environmental Science
    Bulletin of Volcanology
  • 2002
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