[S-EM14] Electric, magnetic and electromagnetic survey technologies and scientific achievements

[SEM14-P14] Forward modeling of the EM-ACROSS at Inferno Crater Lake, New Zealand

*北岡 紀広¹、小川 康雄¹、石須 慶一²、南 拓人³、Caldwell Grant⁴、Kirkby Alison⁴ (1.東京工業大学、2.兵庫県立大学、3.神戸大学、4.GNS Science)

キーワード：電磁アクロス、インフェルノクレーターレイク、順問題

Volcanic activity is interpreted to occur with the movement of fluids in the subsurface. Therefore, observing and monitoring the fluid-sensitive resistivity structure is important in the study of volcanic eruption prediction. A previous study (Legaz et al. 2009) showed that the Inferno Crater Lake on the North Island of New Zealand has cyclic resistivity variations due to a two-phase layer in the lower part of the lake. Therefore, our group conducted EM-Accurately Controlled Routinely Operated Signal System (EM-ACROSS) observations around the Inferno crater lake to observe the resistivity structure.
In this study, we developed a forward problem analysis code for the EM-ACROSS method. In this presentation, we analyze a model of the Inferno Crater Lake and show that the shape of the two-phase region can be identified from the simulated data.