Active Seismic Source Experiment in Sakurajima Volcano in 2019 and Comparison with the Previous Experiments

We conducted an active seismic experiment in Sakurajima volcano in December 2019, three years after the similar experiment that was conducted in 2016. We deployed 185 temporary seismic stations, most of which were installed at the same place as in 2013 and 2016. Eight and two explosive shots with 20 and 100 kg charges, respectively, were detonated in December 5, 2019. The 2019 shot locations differ from 0.4 to 12 m from the corresponding previous shot locations. We successively observed the all explosions during nighttime nine hours continuous recording. We examine reflection phases on the seismic records that obtained by the previous and 2019 experiment to detect temporal change of subsurface seismic structure beneath Sakurajima volcano.