Bernard Marty has made major contributions to our understanding of the origins of volatile elements in the terrestrial planets. One could perhaps highlight four areas, centered on neon, carbon, nitrogen, and xenon. In parallel with Sarda and others, he showed that the neon isotopic composition of oceanic basalts is light relative to the atmosphere and argued that either the atmosphere was residual to a major fraction of lost volatiles or it was added later. He went on to show that some plume basalts have even higher 20Ne/22Ne than previously thought and used this to argue for a component of solar neon in the Earth. Using C/3He ratios of basalts, he estimated the mantle budget for carbon and demonstrated that budgets in arcs are dominated by recycling. With Dauphas he also made the observation that the nitrogen budget of oceanic basalts correlates with 40Ar/36Ar and used this to infer that nitrogen in the mantle was dominated by subduction of clays. He also made groundbreaking discoveries of the zoned nitrogen isotopic composition of the solar system based on Genesis samples. What is most spectacular is his recent work on xenon, where he and his team have made major inroads into long-standing problems. Working on early sediments, he found evidence that the fractionated isotopic composition of the atmosphere has become more so over time and reflects progressive losses, possibly from early UV irradiation. His well gas studies resolved chondritic xenon in the mantle. Finally, with analyses from Comet 67P sampled by Rosetta, he showed that Pepin’s original prediction of U-Xe, the anomalous isotopic composition of Earth’s primordial xenon, is a feature of comets, adding powerful new evidence for a cometary component in heavy noble gases. For these and other contributions, Bernard Marty is an extremely worthy recipient of the 2017 Bowen Award.—Alexander Halliday, University of Oxford, United Kingdom
I am deeply honored to receive the prestigious Bowen Award, and I would like to thank the people who nominated me, the awards committee and all at AGU, for their selfless efforts. I am particularly indebted to Alex Halliday, who has always been keeping his eyes wide open to the magical mystery tour that is the geochemistry of noble gases. I was first introduced to this marvelous field by Minoru Ozima in Tokyo, and I have been inspired by some prominent scientists along my way, including Francis Albarède, Chris Ballentine, Keith O’Nions, Yuji Sano, Igor Tolstikhin, and many others in Paris, Cambridge, and Nancy. I have had the chance to work with fantastic colleagues, students, and postdocs at Centre de Recherches Pétrographiques et Géochimiques (CRPG) Nancy, and especially with Pete Burnard, with whom we developed a state-of-the-art noble gas laboratory at CRPG. Pete was a great noble gas geochemist as well as a true human being. I thank Annie, Louise, and Edwige for personal balance in a life busy with science.
The noble gases are fantastic tracers whose chemical inertness and radiogenic isotopes provide a quantitative approach for investigating mass balance at planetary scales. Their origins in planets have been traced back, thanks to their diverse cosmochemical signatures. However, there remained the need to calibrate “useful” volatile elements, such as water, carbon, and nitrogen, to noble gases to gain insights into their origins and cycles, something I have tried to do throughout my career. Interestingly, none of my research has been directly related to mineralogy and petrology, so I feel particularly humble and blessed to receive an award named after a petrologist as great as Norman Bowen, illustrating to me the fact that in science, our tools do not represent the end of the story but are instead keys for unlocking some of the universe’s mysteries.
—Bernard Marty, University of Lorraine, Nancy, France