Formation and evolution of the uppermost mantle of oceanic plate and island arc based on natural samples of ultramafic-mafic rocks

Ultramafic rocks, i.e., peridotites and pyroxenites, occur in a variety of tectonic settings on Earth. rocks can form as accumulation mafic minerals from basaltic to komatiitic melts be major component the Earth's mantle. The origin history ultramafic are expected provide information processes partial melting melt migration/extraction mantle evolution geologic units containing rocks. I study metamorphic belts, ocean floor, sections ophiolites. My career began with Horoman Peridotite Complex Hidaka belt Japan. associated body record very complex evolutionary conditions crustal conditions. It is difficult constrain setting affecting events Complex. On other hand, section ophiolites abyssal directly recovered floor melt-rock interactions used their setting, or at least analogs these settings. Studies Oman ophiolite by Japanese groups literature studies suggest that many later modified subduction-related magmatism. Several being studied elucidate maturing process Simple extraction adiabatically upwelling beneath mid-ocean ridge. In fact, ridges provided unique opportunity processes. Comparison arc regions (fore back arc) key understand differences magmatic two regions. Ocean science research vessels has well-defined working hypothesis only addressed direct sampling seafloor. To crucial issue Earth why plate tectonics occurs Earth, it essential life oceanic lithosphere its birth subduction into Direct drilling solving this issue. would like emphasize members Japan Association Mineralogical play an role leading analyses rock samples Rock seafloor any methodology, well anywhere should published papers, data help integrate knowledge about planet future.