Sat. Jun 5, 2021 5:15 PM - 6:30 PM Ch.14

convener:Eiji Ohtani(Department of Earth and Planetary Materials Science, Graduate School of Science, Tohoku University), Saeko Kita(International Institute of Seismology and Earthquake Engineering, BRI), Michihiko Nakamura(Division of Earth and Planetary Materials Science, Department of Earth Science, Graduate School of Science, Tohoku University), Bjorn Mysen(Geophysical Laboratory, Carnegie Inst. Washington)

The mass transfer depends on properties of the Earth's materials and geodynamic processes including cold slab subduction and magmatism due to hot plume activity. The mass transfer processes are imaged by geophysical observations such as seismic tomography and electrical conductivity profiles. One of the most important processes to transport volatiles is the slab subduction. The degree of hydration and dehydration in the slab is essential to evaluate amounts of volatiles transported into the deep mantle. Hydration and dehydration in the slab directly related to slab earthquakes, deformation of the slabs, and the arc magmatism. The fate of the fluid dehydrated in the deep slab is also a debated issue since permeability at the depth may be small, and the fluid might be trapped in the slabs and transported in the deep earth's interior at that depths without escaping to the mantle wedge. Recent seismic tomographic studies of the slab revealed direct observations of hydration and dehydration sites in the slabs. There exists growing evidence for alteration and hydration of the old lithosphere due to fracturing and Putit spot volcanisms which affect the volatile transport into the deep mantle due to slab subduction. The mass transfer to the surface can also be observed as the volcanic eruption in which phase separation of magma and fluid, and crystallization during the magma ascent controls the type of eruptions. The proposed session will focus on those phenomena including laboratory experiments, numerical modeling, and geophysical and geochemical observations including physical and chemical properties of magma and fluid, and geophysical imaging of various scales including seismic tomography of the descending slabs, and monitoring of near surface processes of volcanic eruptions. Contributions to any of these subjects are encouraged. We also encourage papers stimulating an interdisciplinary collaboration relating to establishment of the SEDI-Japan community.