Japan Geoscience Union Meeting 2015

Presentation information


Symbol M (Multidisciplinary and Interdisciplinary) » M-IS Intersection

[M-IS32] Drilling Earth Science

Sun. May 24, 2015 6:15 PM - 7:30 PM Convention Hall (2F)

Convener:*Saneatsu Saito(Japan Agency for Marine-Earth Science and Technology), Katsuyoshi Michibayashi(Institute of Geosciences, Shizuoka University), Tetsuro Hirono(Department of Earth and Space Science, Graduate School of Science, Osaka University), Keita Umetsu(Japan Agency for Marine-Earth Science and Technology)

6:15 PM - 7:30 PM

[MIS32-P04] High temperature metamorphism recorded on chromitite samples in drilling cores from ocean floor

*Natsue ABE1, Yumiko HARIGANE2 (1.R&D Ocean Drilling Science, JAMSTEC, 2.Institute of Geology and Geoinformation, AIST)

Keywords:chromitite, IODP Exp. 345, high temperature metamorphism, Moho transition zone, oceanic crust, ODP Leg 209

Metag-gabbro and some serpentinites are not only extremely altered, but also metamorphosed at high temperature up to mid-amphibolite facies. Chromian spinel included in those samples, which is normally well preserved under the condition of ocean floor metamorphism, also metamorphosed into chrome-bearing magnetite and/or magnetite. The crystal orientation varies inside a grain with chemical modification of the metamorphism. We discuss the possibility of such high temperature metamorphism in the deep oceanic plate.