Muographic Observation System used for imaging a magmatic plug in Sakurajima volcano

László Oláh1・Hiroyuki K.M. Tanaka1・Takao Ohminato1・Gerg˝o Hamar2・ Dezs˝o Varga2
1Earthquake Research Institute, University of Tokyo,2Wigner Research Centre for Physics, Budapest
Geophysical Research Letters, 46, 10,421-10,424, doi:10.1029/2019GL084784
First Published: 06 September 2019

Muography is an imaging technique that provides information about the amount of material across kilometer-thick geological structures by the measurement of the yield of cosmic rays, similarly to X-raying of human body. We applied muography to capture two muon images of Minamidake and Showa craters of Sakurajima volcano before and after the shift of eruption activities occurred between the two craters at the end of 2017. The comparison of the images revealed the presence of increased material across the activated Minamidake and beneath the deactivated Showa crater. Muography detected the formation of a magma plug in the conduit of Showa crater that was not detected earlier by any other geophysical technique. These results demonstrate the applicability of cosmic muon imaging for monitoring of magma movements inside active volcanoes.