Effects of topography on facies and compositional zonation in caldera-related ignimbrites

G. A. Valentine, K. H. Wohletz, S. W. Kieffer

Research output: Contribution to journalArticlepeer-review


Large-scale fluid dynamical processes during explosive eruptions within calderas are examined numerically by solving the full set of two-phase hydrodynamic equations with a topographic barrier, representing the rim of a caldera. The effect of the caldera rim on eruption dynamics depends on the relative locations of the rim and the impact zone where tephra collapsing from the eruption column strikes the ground. The distance of the impact zone from the vent is proportional to the collapse (fountain) height of the eruption column. Three significantly different eruption patterns have been observed in the simulations. The numerical models suggest several processes that cause the formation of multiple cooling and flow units in deposits outside a caldera from a single eruption of steady discharge. -from Authors

Original languageEnglish (US)
Pages (from-to)154-165
Number of pages12
JournalGeological Society of America Bulletin
Issue number2
StatePublished - 1992
Externally publishedYes

ASJC Scopus subject areas

  • Geology


Dive into the research topics of 'Effects of topography on facies and compositional zonation in caldera-related ignimbrites'. Together they form a unique fingerprint.

Cite this