[S-VC26] Active Volcanism

[SVC26-10] Investigation of ground deformation due to a pressure source resembling the geometry of the low S-wave velocity region beneaththe Aira caldera.

*Daisuke Miki¹, Tomoki Tsutsui¹, Masato Iguchi¹ (1.Sakurajima Volcano Research Center, Disaster Prevention Research Institute, Kyoto University)

Keywords:Aira caldera, ground deformation, geometry of pressure source

We calculated the ground deformation due to a polyhedron pressure source resembling the geometry of the low S-wave velocity region beneath the Aira caldera, using a FEM model. This model is considered to be more compatible with recent seismological findings than conventional models such as the Mogi model. The displacements calculated from the FEM model generally agree with the GPS and level survey observations as much as the Mogi model, and the residuals tend to be smaller than the Mogi model at stations on the east and north sides of the Aira caldera.