2021 Annual Meeting of Japan Association of Mineralogical Sciences (JAMS)

Presentation information

Oral presentation

R6: Plutonic rocks, volcanic rocks and subduction factory

Thu. Sep 16, 2021 9:30 AM - 12:00 PM Zoom Session 2

Chairperson:Tatsuhiko Kawamoto(Shizuoka University), Atsushi Kamei(Shimane University), Masao 伴 Ban(Yamagata University)

11:00 AM - 11:15 AM

[R6-06] Architecture of the lower crust beneath the fast-spreading axis of the Oman Ophiolite deduced from the ICDP Oman Drilling

*Susumu Umino1, Yuki Kusano2, Osamu Ishizuka2, Takahiro Fudai3, Akihiro Tamura1, Tomoaki Morishita1 (1. Kanazawa Univ., 2. GSJ, AIST, 3. Pacific Cement)

Keywords:Oman ICDP, magma chamber, fast-spreading ridge, upper gabbro, layered gabbro

Lower crustal gabbros exposed and the core samples obtained by the ICDP Oman drilling program in Wadi Gideah, southern Oman Ophiolite, were analyzed for bulk and mineral chemistry.

On the basis of field observations and the bulk and mineral compositions, the glower crustal gabbros in Wadi Gideah are mostly of foliated gabbros, that crystallized in the high-level axial melt lens and were transported downward through the mushy lower crust before having been frozen-in as gabbros.