HR: 0800h
AN: G51A-0048    [Abstracts]
TI: Quasi-Static Thermoelastic Deformation in an Elastic Half Space: Theory and Application to InSAR Observation at Izu-Oshima Volcano, Japan
AU: * Furuya, M
EM: masato@colorado.edu
AF: Earthquake Research Institute, University of Tokyo, Yayoi 1-1-1, Tokyo, 1130032 Japan
AU: * Furuya, M
EM: masato@colorado.edu
AF: CIRES and Department of Physics, University of Colorado at Boulder, CB390, Boulder, CO 80309 United States
AB: We derive closed analytical solutions for a quasi-static thermoelastic deformation response to instantaneous point and spherical heat sources in an elastic half space, extending the result by Furuya (2004). We examine the spatial and temporal evolution of thermoelastic deformation for point and spherical heat sources. We applied the solution to a radar interferometric observation of post-eruptive deformation associated with the 1986 fissure eruption at Izu-Oshima volcano, Japan. Assuming a spherical heat source at a depth of 240~m with a volume of 1.15$\times10^{7}$ m$^{3}$ and a temperature offset $10^{3}$ K, the predicted rate of post-eruptive ground movement agrees with the observed rate within observational errors. Also, the same parameter values allow us to compute the co-eruptive ground displacement by the effect of mass intrusion, whose amplitude is consistent with the observed height (45~m) of the newly formed cone. The derived solutions can be applied to transient ground displacements observed at active volcanos, and allow us to evaluate the heat amount of magma intruded at very shallow depth.
DE: 8434 Magma migration
DE: 8494 Instruments and techniques
DE: 1208 Crustal movements--intraplate (8110)
SC: Geodesy [G]
MN: 2004 AGU Fall Meeting