Eiji Ohtani received the 2007 N. L. Bowen Award at the 2007 AGU Fall Meeting in San Francisco, Calif. The award recognizes outstanding contributions to volcanology, geochemistry, or petrology.
Eiji Ohtani is indisputably the most prominent leader in the experimental studies of properties of Earth materials, particularly the melting relationships and the properties of melts under high pressures and temperatures. Eiji started his brilliant career in Mineo Kumazawa’s lab at Nagoya University in the early 1970s. Mineo Kumazawa is one of the pioneers of large-volume high-pressure devices (others include Naoto Kawai and Syun-iti Akimoto), and Eiji played a major role as a young student in establishing new techniques of high-pressure and high-temperature experiments using a large-volume apparatus. His reputation was established already in the early 1980s based on his seminal papers on the melting of fayalite and forsterite under high pressures (to 20 gigapascals).
Soon after his Ph.D., Eiji moved to Australian National University (Ted Ringwood’s lab) as a research fellow (I also applied for the research fellow position with Ted Ringwood, but Ted, of course, made the right decision as usual), and there Eiji established a multianvil lab from which a number of important results were found not only by Ohtani himself but also by Tetsuo Irifune and Takumi Kato. After coming back from ANU, Eiji built two high-pressure labs in Japan, first at Matsuyama (Ehime University) and next at Sendai (Tohoku University), and started an even more impressive and productive career. He has established an “army” of students and postdocs (his “army” is so big that I often wonder if it is “constitutional”) and has conducted a truly impressive series of experimental studies not only on melts and melting relationships but also on other related topics such as the stability of hydrous phases, kinetics of phase transformation, diffusion of ions under high pressures, etc. In fact, it is impossible to write a paper on melting or melts in the deep Earth without citing Eiji Ohtani’s papers. Therefore Eiji’s contributions fit very nicely with the description of the Bowen Award: a series of papers which, taken together, constitute “an outstanding contribution to volcanology, geochemistry and petrology.”
Eiji is full of energy, and I do not see any sign of him slowing down in his scientific activities. At the same time, he is a quiet and modest person. I am really pleased that AGU has recognized his fundamental contributions to volcanology, geochemistry, and petrology by awarding him the Bowen Award. Congratulations, Ohtani-san!
—Shun-Ichiro Karato, Yale University, New Haven, Conn
Thank you, Shun-Ichiro Karato, for your warm and generous citation. It is my great pleasure to receive the award that bears the name of Norman L. Bowen, who is the real pioneer and hero in Earth science.
As an undergraduate student at Tohoku University, I visited Hokkaido, Japan, in 1972 for a field survey of the Horoman ultramafic complex supervised by Ken-Ichiro Aoki, one of the pioneers in upper mantle petrology. I was so impressed by the beautiful and fresh peridotite outcrops, and I wanted to understand the mystery operating in the Earth’s deep interior. Since I was assured that high-pressure works are vital to clarifying the Earth’s deep interior, I decided to study at Mineo Kumazawa’s laboratory at Nagoya University as a graduate student. This is the reason I am now working as a professional in studying the Earth’s deep interior.
I struggled to develop a large volume press during the graduate course, and in 1979 I finally successfully made some experiments on melting of silicate minerals to 15 gigapascals. The experiments could be applied to a deep magma ocean, which was expected theoretically at that time by Wetherill, Hayashi, and Kaula in the primordial Earth.
I spent 2 years, 1983 and 1984, at the Australian National University as a research fellow in Ted Ringwood’s group. It was the most fruitful time in my research career, and I enjoyed research there by intensive discussions with young active postdocs, many of whom are now working as top runners in our science community. I spent plenty of time thinking about magma ocean issues and a possible crystal-melt density crossover, a current hot issue in geodynamics. I also enjoyed working with excellent technicians Alan Major and Bill Hibberson installing a large volume press.
In 1995, I spent 8 months at the Bayerisches Geoinstitute, University of Bayreuth. I was impressed by the friendly and active atmosphere of the institution, directed by Fritz Seifert and Dave Rubie. After my stay in Bayreuth, we continued to make intensive exchanges of young people and collaborations, such as study on shocked meteorites with Ahmed El Goresy, which was started by fruitful discussions with Tom Sharp during my stay in Bayreuth.
Finally, I would like to thank all of the excellent colleagues and brilliant students of my department at Tohoku University who made fruitful collaborations in my research career.
—Eiji Ohtani, Tohoku University, Sendai, Japan