Japan Geoscience Union Meeting 2018

Presentation information

[JJ] Poster

S (Solid Earth Sciences) » S-VC Volcanology

[S-VC41] Active Volcanism

Wed. May 23, 2018 1:45 PM - 3:15 PM Poster Hall (International Exhibition Hall7, Makuhari Messe)

convener:Yuta Maeda(Nagoya University), Takahiro Miwa(National research institute for earth science and disaster prevention), Yosuke Aoki(東京大学地震研究所, 共同), Takeshi Nishimura(Department of Geophysics, Graduate School of Science, Tohoku University), Takahiro Ohkura(Aso Volcanological Laboratory, Institute for Geothermal Sciences, Graduate School of Science, Kyoto 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)

[SVC41-P05] Subsurface Resistivity Imaging by TDEM Method in Nasudake volcano

*Toshikazu Tanada1, Yoichi Nakamura2 (1.National Research Institute for Earth Science and Disaster Prevention, 2.Utsunomiya University, Honorary professor)

Keywords:Nasudake, volcano, Resistivity

Resistivity structure survey of shallow part by TDEM method was carried out around Cyausu-dake (1915 m) of active volcano, Nasudake, to investigate the relationship with fumarolic area and geological structure. Two survey lines were set in the east-west (5.5 km) and the north-south direction (3.1 km) where the intersection of Minenocyaya-ato of the northern side of Cyausu-dake.
On the western side from Minenocyaya-ato of the east-west survey line, it is shown that resistivity structure has a two-layer structure of low- medium resistivity, whereas on the east side it was a three layer structure with low- medium- high resistivity. The low resistivity value layer on the eastern side of the survey line is considered to indicate the fluidized layer of hot water because the source of the hot spring is dotted in the surrounding area.
On the north - south survey line, the resistivity structure was roughly a two - layer structure with low - medium resistivity.In the fumarolic area, the layer thickness of low resistivity was thin, and the medium resistivity area continued until the analysis depth (altitude 800 m).