S2: Water Rock Interaction (Special Session)

[S2-04] Antigorite vein formation and fluid flow in the crust-mantle transition zone in the Oman ophiolite

[Presentation award entry]

*Kazuki Yoshida¹, Atsushi Okamoto¹, Ryosuke Oyanagi², Masao Kimura³ (1. Tohoku Univ., 2. Kokushikan Univ., 3. KEK)

Keywords:Serpentinization, Oman ophiolite, Antigorite, Fluid flux

Antigorite is an important mineral for the estimation of the pressure/temperature condition during serpentinization. In this study, we investigated completely serpentinized dunite with antigorite veins from the crust-mantle transition zone of the Oman ophiolite. We investigated vein structures, mass transport, and fluid flux during the antigorite vein formation. The results suggest that alkaline fluid moved through the crust-mantle transition zone during the antigorite vein formation.