[S-VC28] Active Volcanism

[SVC28-14] A preliminary report of a pilot experiment for the sustainable repeating seismic experiment in Aira Caldera, Japan.

*Tomoki Tsutsui¹, Takeshi Tameguri¹, Daisuke Miki¹, Masato Iguchi¹, Masanao Shinohara² (1.DPRI, Kyoto University, 2.ERI, University of Tokyo)

Keywords:Aira Caldera, Monitoring method, Controlled source seismology

A pilot experiment for a feasibility study of the sustainable repeating seismic experiments in Aira Caldera is presented. Aira Caldera locates in the south end of Kyushu island, Japan, and hosts Sakurajima Volcano at the south margin. Aira Caldera had erupted on 29ka with huge volume of pyroclastic material, however, the caldera is still active. Active ground deformations have been observed in the margin of the caldera, which suggests activity of the caldera associating with Sakurajima Volcano. Direct monitoring methods are necessary in order to assess level of volcanic activity in the caldera. The repeating seismic experiment has proposed as one of progressive methods to monitor underground volcanic activity of the caldera. Foundation and feasibility of new method is tested through the pilot experiment. The experiment contains airgun shooting as a seismic source in one side of the caldera and a seismic array as the receivers in another side of the caldera. The experiment was successful and provides what is enough for sustainability of the experiment. This research is supported by the safety research fund from Nuclear Regulation Authority.