The thickness, volume and grainsize of tephra fall deposits

  title={The thickness, volume and grainsize of tephra fall deposits},
  author={David M. Pyle},
  journal={Bulletin of Volcanology},
  • D. Pyle
  • Published 1989
  • Geology
  • Bulletin of Volcanology
An improved empirical method for the plotting of field data and the calculation of tephra fall volumes is presented. The widely used “area” plots of ln(thickness) against ln(isopach area) are curved, implying an exponential thinning law. Use of ln(thickness)−(area)1/2 diagrams confirm the exponential dependence of many parameters (e.g. thickness, maximum and median clast size) with distance from source, producing linear graphs and allowing volumes to be calculated without undue extrapolation of… 
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