S2: Water Rock Interaction (Special Session)

[S2-03] Sr isotopic variation of the CM1A core samples of Oman ophiolite

*Masako Yoshikawa¹, Tomoyuki Shibata¹, Asyraf Mohamed Aminuddin², Ryoko Senda³, Tomoaki Morishita² (1. Hiroshima Univ., 2. Kanazawa Univ., 3. Kyushu Univ.)

Keywords:Oman drilling project, CM1A site, crust-mantle transition zone, Sr isotopic ratio

We analyzed Sr isotopic ratios of gabbros and peridotites (dunite and harzburgite) collected from the drilling CM1A site that penetrates the crustal-mantle boundary of the Wadi Tayin massif in the southern Oman ophiolite. The Sr isotope ratios show good correlation with degree of alteration and estimated Sr isotope ratio of the solution circulated in peridotites is around ⁸⁷Sr/⁸⁶Sr = 0.7040.