JpGU-AGU Joint Meeting 2017

Presentation information

[EE] Poster

S (Solid Earth Sciences) » S-VC Volcanology

[S-VC46] [EE] Transition mechanism of volcanic eruptions

Wed. May 24, 2017 1:45 PM - 3:15 PM Poster Hall (International Exhibition Hall HALL7)

convener:Takeshi Nishimura(Department of Geophysics, Graduate School of Science, Tohoku University), Satoshi Okumura(Division of Earth and Planetary Materials Science, Department of Earth Science, Graduate School of Science, Tohoku University), Tomofumi Kozono(Department of Geophysics, Graduate School of Science, Tohoku University)

[SVC46-P08] Hypocenters of earthquakes associated with rapid magma intrusion into Sakurajima volcano in August 2015 - Estimation by the amplitude source location method -

*Haruhisa Nakamichi1, Masato Iguchi1, Takeshi Tameguri1 (1.Sakurajima Volcano Research Center, Disaster Prevention Research Institute, Kyoto University)

Keywords:Sakurajima volcano, Hypocenter, Earthquake swarm

We estimated 250 hypocenters of earthquakes that occurred on August 15, 2015 beneath Sakurajima Volcano, southwest Japan by using the amplitudes source location (ASL) method. A plot of residuals for a hypocenter by the ASL method shows that horizontal locations were well constrained compared with the depths. The epicenters of the earthquakes distribute in and around the dike source which is estimated by geodetic measurements (See Figure). However, the depths of the earthquakes are poorly constrained and widely distribute at -1 to 6 km below sea level. The temporal change of the hypocentral distribution is weakly seen and should be carefully examined.