# The thickness, volume and grainsize of tephra fall deposits

@article{Pyle1989TheTV,
title={The thickness, volume and grainsize of tephra fall deposits},
author={David M. Pyle},
journal={Bulletin of Volcanology},
year={1989},
volume={51},
pages={1-15}
}
• 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…
686 Citations
Estimating the volume of tephra deposits: A new simple strategy
• Geology
• 2012
Volume determination of tephra deposits is necessary for the assessment of the dynamics and hazards of explosive volcanoes. Several methods have been proposed during the past 40 years that include
Total grain-size distribution and volume of tephra-fall deposits
• Geology
• 2005
On 17 June 1996, Ruapehu volcano, New Zealand, produced a sustained andesitic sub-Plinian eruption, which generated a narrow tephra-fall deposit extending more than 200 km from the volcano. The
A statistical method for determining the volume of volcanic fall deposits
• Geology
Bulletin of Volcanology
• 2013
Volumes of tephra-fall deposits are difficult to determine due to the commonly poor preservation of proximal and distal areas of the deposit. Typically, these volumes are found by extrapolating
Grain-size variation of tephra derived from volcanic umbrella clouds
AbstractThe relationships among the thickness and grain-size of tephra-fall deposits and the volumetric flow rate of their source umbrella clouds are analytically obtained. The logarithm of the ratio
Sedimentation of tephra by volcanic plumes. Part 2: controls on thickness and grain-size variations of tephra fall deposits
• Geology
• 1992
A model for sedimentation from turbulent suspensions predicts that tephra concentration decreases exponentially with time in an ascending volcanic column and in the overlying umbrella cloud. For
Ignimbrite morphology and the effects of erosion: a New Zealand case study
Ignimbrite morphology, previously generalised using aspect ratios, is here quantified as the relationships between the various thicknesses of material forming an ignimbrite and the areas and volumes
Modeling thickness variability in tephra deposition
• Geology
Bulletin of Volcanology
• 2013
The attenuation of tephra fall thickness is most commonly estimated after contouring isolated and often irregular field measurements into smooth isopachs, with varying degrees of subjectivity
Another look at the calculation of fallout tephra volumes
• Geology
• 1992
The calculation of volumes of fallout tephra layers is difficult because of the nonlinear dependence of thickness on area and because of the extrapolations required at the vent and in distal regions.

## References

SHOWING 1-10 OF 47 REFERENCES
Maximum size, median diameter, and sorting of tephra
The many variables involved in the production, ejection, transportation, and deposition of pyroclastic fragments (tephra) with wide ranges in size, density, and shape are complex, but amenable to
Grain-Size Characteristics of Pyroclastic Deposits
Pyroclastic fall and flow deposits occupy two distinct fields on an $$Md_{\phi}/\sigma_{\phi}$$ plot (Inman parameters), and a contoured diagram is given based on 1,600 samples to facilitate
Plinian airfall deposits of basaltic composition
Two widespread scoria-fall deposits, locally known as the Fontana Lapilli and San Judas Formation, are demonstrated to have issued from Masaya Caldera Complex, Nicaragua, and to be the first
Quantitative models of the fallout and dispersal of tephra from volcanic eruption columns
• Environmental Science, Geology
• 1986
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
Influence of particle aggregation on deposition of distal tephra from the MAy 18, 1980, eruption of Mount St. Helens volcano
• Geology
• 1982
The May 18, 1980, eruption of Mount St. Helens (MSH) produced an extensive ashfall deposit in Washington, Idaho, and Montana with a minumum volume of 0.55 km3 (tephra). An unusual feature of the
Plinian eruptions and their products
Plinian eruptions are amongst the most powerful of explosive volcanic events, and the extensive pumice deposits which they produce have an exceptionally wide dispersal because of the great eruptive
Characteristics of widespread pyroclastic deposits formed by the interaction of silicic magma and water
• Geology
• 1978
We have recognized a type of pyroclastic deposit formed by the interaction of water and silicic magma during explosive eruptions. These deposits have a widespread dispersal, similar to plinian