[S-CG62] 巨大地震と火山活動：火山活性化過程の基礎研究

[SCG62-09] 島弧火山の深部構造

*中島 淳一¹ (1.東京工業大学大学院理工学研究科地球惑星科学専攻)

キーワード：火山、東北、上昇流

The subduction zone system on the Earth is over 40,000 km long. The active processes –brittle deformation, metamorphism, convection and volcanism– beneath volcanic arcs are all linked with slab-derived fluids. Here I review seismological observations in subduction zones and show that a low-velocity zone is observed in the mantle wedge beneath all volcanic arcs. Interestingly, geometries of the low-velocity zone, however, vary depending on the dip and age of the subducting slab. I also present deep crustal structure in NE Japan and discuss how the crustal structure changes along the volcanic front, providing a clue to understand deep origins of arc magmas and ongoing processes beneath volcanic arcs.