Rights statement: ©2012. American Geophysical Union. All Rights Reserved
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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Particle-water heat transfer during explosive volcanic eruptions
AU - Woodcock, D. C.
AU - Gilbert, Jennie
AU - Lane, S. J.
N1 - ©2012. American Geophysical Union. All Rights Reserved
PY - 2012/10/11
Y1 - 2012/10/11
N2 - Thermal interaction between volcanic particles and water during explosive eruptions has been quantified using a numerical heat transfer model for spherical particles. The model couples intraparticle conduction with heat transfer from the particle surface by boiling water in order to explore heat loss with time for a range of particle diameters. The results are combined with estimates of particle settling times to provide insight into heat removal during eruption from samples of volcanic particles produced by explosive eruption. Heat removal is restricted by resistance to heat transfer from the volcanic particles with intraparticle thermal conduction important for large particles and surface cooling by boiling dominating for small particles. In most cases, volcanic particles approach thermal equilibrium with the surrounding fluid during an explosive eruption. Application of the results to a sample from the Gjalp 1996, Iceland eruption indicates that, relative to 0 degrees C, 70-80% of the heat is transferred from the particles to boiling water during the settling time before burial in the stratigraphic succession. The implication is that, for subglacial explosive eruptions, much of the heat content of the magma is coupled into melting ice extremely rapidly. If all particles of the Gjalp 1996 deposit were cooled to the local boiling point by the end of the eruption then approximately 78% of the initial heat content was removed from the erupting magma during the eruption. This is consistent with calorimetric calculations based on volumes of ice melted during and after the eruption.
AB - Thermal interaction between volcanic particles and water during explosive eruptions has been quantified using a numerical heat transfer model for spherical particles. The model couples intraparticle conduction with heat transfer from the particle surface by boiling water in order to explore heat loss with time for a range of particle diameters. The results are combined with estimates of particle settling times to provide insight into heat removal during eruption from samples of volcanic particles produced by explosive eruption. Heat removal is restricted by resistance to heat transfer from the volcanic particles with intraparticle thermal conduction important for large particles and surface cooling by boiling dominating for small particles. In most cases, volcanic particles approach thermal equilibrium with the surrounding fluid during an explosive eruption. Application of the results to a sample from the Gjalp 1996, Iceland eruption indicates that, relative to 0 degrees C, 70-80% of the heat is transferred from the particles to boiling water during the settling time before burial in the stratigraphic succession. The implication is that, for subglacial explosive eruptions, much of the heat content of the magma is coupled into melting ice extremely rapidly. If all particles of the Gjalp 1996 deposit were cooled to the local boiling point by the end of the eruption then approximately 78% of the initial heat content was removed from the erupting magma during the eruption. This is consistent with calorimetric calculations based on volumes of ice melted during and after the eruption.
KW - boiling water
KW - heat transfer
KW - numerical model
KW - volcanic particle
UR - http://www.scopus.com/inward/record.url?scp=84867648150&partnerID=8YFLogxK
U2 - 10.1029/2012JB009240
DO - 10.1029/2012JB009240
M3 - Journal article
VL - 117
JO - Journal of Geophysical Research: Solid Earth
JF - Journal of Geophysical Research: Solid Earth
IS - B10
M1 - B10205
ER -