Citation for Marion Garçon

Marion Garçon, winner of AGU’s 2019 Hisashi Kuno Award
Marion Garçon

Marion Garçon, starting with her Ph.D. thesis, has made seminal and definitive contributions to geochemistry. Her thesis was a milestone in our understanding of the so-called “zircon effect” in sediments. This effect causes the Lu/Hf ratios of pelagic clays to be systematically higher than the corresponding ratio in the continental sediment sources. Hafnium in sediments is sequestered in zircons, and most of those zircons don’t make it into the deep sea. Marion showed where and how this zircon sorting starts in rivers long before the sediments are carried out to sea. This led to greatly improved understanding of how mineral sorting fractionates the chemical and isotopic compositions of sedimentary material.

Marion followed this with a definitive study of the role of accessory minerals in dominating the isotopic composition of sediments, not only for zircons but also for allanite and monazite, as well as K-feldspar. Next, she showed how erosion and transport biases the composition of sediments: In a large-river water column, the near-surface suspended sediments overrepresent the mafic portion of the source region, while the near-bottom sediments are biased toward the more felsic source materials.

In a recent paper, Marion delineated the major source components of classic early Archean Barberton sediments from South Africa. She showed that the detrital sedimentary component derived from a crust that is 300–400 Ma older is dominated by mafic–ultramafic sources. Overall, she showed that the South African Archean crust has about 60% SiO2 and is thus significantly more mafic than more recent continental crust.

Most recently, she has contributed an exhaustive investigation of the mass spectrometric methodology needed to achieve the “ultimate” precision for Nd isotope ratio measurements, one which is limited only by counting errors.

I stand in awe of the originality, thoroughness, and exceptional quality of Marion’s work.

—Albrecht W. Hofmann, Max Planck Institute for Chemistry, Mainz, Germany


Thank you, Al, for your support. It is an honor to receive this unexpected award, and I would like to thank all the people involved in my nomination, the Kuno committee, and the Volcanology, Geochemistry, and Petrology (VGP) section for awarding me this prize.

I owe a lot to my Ph.D. adviser, Catherine Chauvel, who introduced me to geochemistry during my master’s. She was a wonderful Ph.D. adviser who passed on to me her passion and rigor of analytical chemistry. Thank you, Catherine, for being so enthusiastic and supportive from the beginning. I would not be here today without you.

Following my Ph.D., I was lucky enough to do a postdoc at Carnegie Institution with Rick Carlson and Steve Shirey, who are incredibly talented researchers, always keen to discuss ideas, results, and analytical issues. I learned a lot from you and thank you for making my Carnegie experience wonderful from both the professional and personal points of view.

I am also grateful to Maud Boyet, who welcomed me with open arms at Clermont-Ferrand and was always very supportive when it came to writing applications, grants, and manuscripts. She is a bright person with a lot of human qualities, and I am very happy to have her as a colleague now. Finally, I thank my colleagues, office mates, and collaborators at Terre, Carnegie, ETH Zürich, and Laboratoire Magmas et Volcans for making my daily working life rich and fun.

Of course, none of this would have been possible without the unconditional support of my wife, Lucie, who coached me on so many talks and interviews. I also thank my parents and parents-in-law, who were always supportive of my professional choices even if they still do not really understand what I do with rocks. I feel very lucky to have you all and our baby girl, Jade.

—Marion Garçon, CNRS Laboratoire Magmas et Volcans, Clermont-Ferrand, France

Citation for Daniel A. Stolper

Daniel A. Stolper, winner of AGU’s 2019 Hisashi Kuno Award
Daniel A. Stolper

It is my pleasure to introduce Daniel Stolper, recipient of the 2019 Kuno Award. This award is given in honor of Hisashi Kuno, who was instrumental in our understanding of subduction zone magmatism, worked with Harry Hess in the years leading to the formulation of the modern theory of plate tectonics, and was an intellectual leader in petrology throughout his career at the University of Tokyo.

Daniel is a worthy recipient of this award for a number of reasons. Most obvious are his recent papers on the evolution of the oxidation state of Earth’s ocean and atmosphere, based on the observed variation through time of the oxidation state of iron in weathered igneous rocks and arc volcanics. This body of work elegantly illuminates the diverse roles of igneous rocks as records and hosts of oxidation and of magmatism as an active part of Earth’s redox cycles.

It is also noteworthy that these studies did not arise from a formal background in igneous petrology, but rather grew organically from Daniel’s training and interests across diverse subjects in the natural sciences. He is a genuine polymath whose contributions span great intellectual breadth and often come about by connecting the insights of one field to the needs of another. Over the past 5 years, Daniel has moved freely between whole-Earth, deep-time geochemistry; cutting-edge analytical technologies; experimental petrology; the geochemistry, petrology, and crystal chemistry of igneous, sedimentary, and metamorphic rocks; petroleum geoscience; Pleistocene climate change; and biology and biochemistry. Every subject he has touched has resulted in novel inventions, incisive reinterpretations of old data, and bold new proposals.

Thank you for joining me in this celebration of Daniel’s receipt of the Kuno Award in recognition of his groundbreaking scholarly contributions to the Earth sciences.

—John M. Eiler, California Institute of Technology, Pasadena


Thank you, John, and thank you to the VGP section for this wonderful honor. My scientific education began at age six when I started going with my father, Ed Stolper, a Caltech geology professor, to weekly Saturday lunches attended by Caltech geology students, postdocs, and professors, including Sam Epstein, Lee Silver, and Dave Stevenson. At these lunches, all topics, from science to pop culture, were debated with vigor. What I remember most is that everyone, no matter their age or background, was treated as an intellectual equal. These lunches shaped two of my core scientific values. First, it is the idea that matters, not from whom it comes. Second, we are in the business of the search for the truth, and intellectual debate is key to this endeavor.

My formal geological training began at Harvard with inspiring classes from Dan Schrag, Paul Hoffman, Ann Pearson, and Andy Knoll. After an amazing year in Don Canfield’s lab, I began graduate school at Caltech working with John Eiler. John served as a role model on how to be both a scientist and a mensch. Finally, I was a postdoc at Princeton with Michael Bender. This was a formative experience in which Michael ingrained in me the importance of rigor. I have been an assistant professor at Berkeley for 3 years and am blessed with supportive colleagues. Although I am often unsure of where my research is headed, these experiences, mentors, and colleagues give me confidence it is headed somewhere.

Finally, I thank my family. My father has immeasurably influenced my scientific principles and values. I especially wish to thank my wife, Leslie, for her unending support and my daughter, Yael, for reminding that there is more to life than work, even if that reminder comes at four in the morning.

—Daniel A. Stolper, University of California, Berkeley


(2020), Garçon and Stolper receive 2019 Hisashi Kuno Award, Eos, 101, Published on 28 September 2020.

Text © 2020. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Text © 2020. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.