[S-EM36_30PO1] Electrical conductivity, Tectono-electromagnetism

[SEM36-P03] Volcano-Loop observation at Kusatsu-Shirane volcano

Yuta HINO¹, *Yasuo OGAWA², Wataru KANDA², Hideaki HASE², Kaori SEKI¹ (1.Department of Earth and Planetary Sciences, Tokyo Institute of Technology, 2.Volcanic Fluid Research Center, Tokyo Institute of Technology)

Keywords:Electromagnetic induction, time domain, loop, volcano, monitoring

We have made successful measurement of time domain electromagnetic signals using transmitting and receiving loops at the same location. This system is being planned to work for monitoring the volcano vent. The test measurement was conducted in the Kusatsu-Shirane volcano where detailed resistivity structure is known by audio-magnetotelluric method. The stepwise waveform was used and off-time response was measured using a transmitting and receiving loop both with 33m radius. The induced voltage was measured from the 0.1ms to 30ms. The observed voltages as a function of time in logarithm were inverted using Occam's algorithm and the model resistivity and resolution of the model were investigated. We also compared the result with those obtained by magnetotelluric method and found that the upper surface layers which have 1d structure are consistent with volcano loop results. We plant to use the system for repeated measurements or continuous monitoring the volcano in the future.