S1: Earth materials science in igneous processes (Special Session)

[S1-02] Native iron formation during mantle metasomatism recorded in a mantle xenolith from Aitutaki island, Cook islands

*Norikatsu Akizawa¹, Kazuhito Ozawa², Wallis Richard Simon², Akihiro Tamura³, Tatsuhiko Kawamoto⁴, Atsushi Yasumoto⁵, Chihiro Ohshima¹, Akira Ishikawa⁶, Tetsu Kogiso⁷ (1. AORI, The Univ. Tokyo, 2. Dept. Earth and Planetary Sci., The Univ. Tokyo, 3. Dept. Earth Sci., Kanazawa Univ., 4. Dept. Geoscience, Shizuoka Univ., 5. Hiruzen, 6. Earth and Planetary Sci., Tokyo Tech., 7. Grad. Sch. Hum. and Environ. Stud., Kyoto Univ.)

Keywords:Native iron, carbonate, carbonatitic metasomatism, garnet

We report geological and geochemical characteristics of a mantle peridotie from Aititaki island, which includes submicrometer-sized native iron grains. Since the mantle peridotite contains calcite vein along tiny (~a few micrometer) crack developped in a chromian spinel grain, we suggest that the mantle peridotite was metasomatized by carbonatitic melts.