TY - JOUR

T1 - Tephra Fallout Models: The Effect of Different Source Shapes on Isomass Maps

AU - Lim, Leng L.

AU - Sweatman, Winston L.

AU - McKibben, Robert

AU - Connor, Charles B.

PY - 2008/2/1

Y1 - 2008/2/1

N2 - Numerous tephra dispersion and sedimentation models rely on some abstraction of the volcanic plume to simplify forecasts of tephra accumulation as a function of the distance from the volcano. Here we present solutions to the commonly used advection–dispersion equation using a variety of source shapes: a point, horizontal and vertical lines, and a circular disk. These may be related to some volcanic plume structure, such as a strong plume (vertical line), umbrella cloud (circular disk), or co-ignimbrite plume (horizontal line), or can be used to build a more complex plume structure such as a series of circular disks to represent a buoyant weak plume. Basing parameters upon eruption data, we find that depositions for the horizontal source shapes are very similar but differ from the vertical line source deposition. We also compare the deposition from a series of stacked circular disk sources of increasing radius above the volcanic vent with that from a vertical line source.

AB - Numerous tephra dispersion and sedimentation models rely on some abstraction of the volcanic plume to simplify forecasts of tephra accumulation as a function of the distance from the volcano. Here we present solutions to the commonly used advection–dispersion equation using a variety of source shapes: a point, horizontal and vertical lines, and a circular disk. These may be related to some volcanic plume structure, such as a strong plume (vertical line), umbrella cloud (circular disk), or co-ignimbrite plume (horizontal line), or can be used to build a more complex plume structure such as a series of circular disks to represent a buoyant weak plume. Basing parameters upon eruption data, we find that depositions for the horizontal source shapes are very similar but differ from the vertical line source deposition. We also compare the deposition from a series of stacked circular disk sources of increasing radius above the volcanic vent with that from a vertical line source.

KW - volcanic plume

KW - eruption column

KW - tephra

KW - volcanic hazard

KW - advection–dispersion

UR - https://digitalcommons.usf.edu/geo_facpub/1057

UR - https://doi.org/10.1007/s11004-007-9134-4

U2 - 10.1007/s11004-007-9134-4

DO - 10.1007/s11004-007-9134-4

M3 - Article

VL - 40

JO - Mathematical Geosciences

JF - Mathematical Geosciences

ER -