[1] Japan Agcy Marine Earth Sci & Technol JAMSTEC, Inst Extra Cutting Edge Sci & Technol Avant Garde, Kochi Inst Core Sample Res, 200 Monobe Otsu, Nankoku, Kochi 7838502, Japan
[2] Japan Agcy Marine Earth Sci & Technol JAMSTEC, Res Inst Marine Resources Utilizat, Submarine Resources Res Ctr, 2-15 Natsushima Cho, Yokosuka, Kanagawa 2370061, Japan
[3] Natl Museum Japanese Hist, Museum Sci Div, Jonaicho 117,Sakura Ku, Chiba 2858502, Japan