Dr. Dennis Kent has made many distinguished contributions to paleomagnetism that have had extensive and fundamental impact in the wider Earth sciences. Dr. Kent is a broad thinker who focuses on the bigger questions in his research field and beyond. A key finding that contributed to the establishment of the central paradigm of the Earth sciences — plate tectonics — is that marine magnetic anomalies provide a record in the seafloor of the sequence of polarity reversals of Earth’s magnetic field. With esteemed colleagues, Kent built on this foundation to develop a geomagnetic polarity timescale that provides a chronology for about the last 120 million years of Earth history. This foundational global geochronology has nearly universal utility and has underpinned our understanding of Earth and its history, particularly concerning the timing and rates of Earth processes. With other esteemed colleagues, Kent has effectively doubled the length of the geomagnetic polarity timescale by extending it beyond the timescale available from ocean crust using astronomical tuning of continental and marine sediments. In addition to these “greatest hits,” Kent has made seminal contributions to understanding diverse issues, including how sediments record paleomagnetic signals, how Earth’s magnetic field behaves while it reverses polarity, how the magnetic signature of ocean crust records reversals and variations of intensity of Earth’s magnetic field, testing the foundational hypothesis of paleomagnetism (the geocentric axial dipole hypothesis), building a chronology of human evolution, correcting sedimentary paleomagnetic records to estimate paleolatitude more reliably, and unraveling puzzles involving global plate tectonics and ancient climatic change. All of these subjects are well-plowed ground, yet Kent has managed to make telling contributions to each with a substantial body of work that touches all aspects of the Earth sciences. In addition to these research contributions, Kent has been an exceptional mentor of younger scientists, many of whom have developed into outstanding researchers. He has also served as a leader of globally important professional organizations, including AGU, and research institutions. Few individuals in geomagnetism, past or present, have made such substantial contributions to the advancement of geophysics. Dr. Dennis Kent is a giant of the Earth sciences and a richly deserving John Adam Fleming Medalist. — Andrew P. Roberts Australian National University Canberra, Australia

I thank Andrew Roberts for his generous remarks and the co-nominators for placing my candidacy in such a favorable light that it was accepted by the committee of AGU to bestow this significant honor in geomagnetism and paleomagnetism. I want to take this opportunity to single out the person most responsible for putting me on the path to a career in science that has led to receiving this honor: my dearly departed mentor, colleague and friend Neil Opdyke. He hired me cold to work in the Paleomagnetics Lab at bucolic Lamont during my senior year at City College. He then somehow managed to get me into the graduate program at Columbia; the attractive offer reached me by telegram on Columbia’s R/V Vema just a month into what should have been a year cruise. I accepted, returned to Lamont, and have basically been here since. It was such a jarringly exciting time and place to be. Drifting continents and plate tectonics, geomagnetic polarity reversals recorded in magnetic anomalies and the magnetostratigraphy of deep-sea sediments, the pacing of Pleistocene ice ages were all ripe topics for exploration using paleomagnetism. Neil was the master; he always knew what was important and provided passionate support for pursuing answers with empirical data generated in his lab. I met my wife, Carolyn, at Lamont, where we were part of a wonderful social and intellectual scene. Neil left me the lab when he departed for a tenured position at the University of Florida in 1980, and this presented me the challenge and ultimate deep satisfaction of mentoring a cadre of graduate students and brilliant postdocs and spinning up field projects with colleagues far and near. In the late 1990s, I joined the tenured faculty at nearby Rutgers University, where a singular pleasure was to teach a large undergraduate course called “Earth and Life Through Time.” The course was designed to satisfy a science requirement for nonscience majors, but it enabled me to expand my research horizons. I was also fortunate to supervise outstanding Ph.D. students, with whom I am still actively working. Wish you were here, Neil, but I thank you in spirit along with Carolyn and family and friends and colleagues for all their support and the good ride that made it possible to arrive at this honor bestowed by AGU, the nonpareil geophysical organization I’ve been associated with for my entire career. — Dennis Kent Columbia University New York, New York

Dennis Kent received the William Gilbert Award at the 2009 AGU Fall Meeting, held 14–18 December in San Francisco, Calif. The award recognizes outstanding and unselfish work in magnetism of Earth materials and of the Earth and planets.  

It is an honor to introduce Dennis Kent, this year’s William Gilbert Award winner. Over the more than 35 years since his first publication, Dennis has poked around in most corners of the science that we do in this section. And when Dennis pokes around, he frequently finds some new pearl of wisdom. He has given us hundreds of treasures in the form of published papers. Early on, he developed a passion for the magnetization of mud. Really, mud. Since then he has studied rock, glass, dust, ice, and smoke (and the last three were all in just one paper). But he doesn’t just study magnetic properties of stuff; he uses those properties to solve problems throughout Earth science. He has contributed to the understanding of wandering poles, evidence for cometary impacts, wiggles of various sorts, and the nature of the geomagnetic field. He played a key role in putting together marine magnetic anomalies, biostratigraphy, isotopic dating, and magnetostratigraphy to build the geological time scale. This humongous effort is his most cited body of work.

But Dennis isn’t simply a paper machine. He is also a role model for all of us. And not just for those of us lucky enough to have been mentored directly by him, but also through his informal advising. He is very generous in providing time in his lab, and he has helped many young scientists with thoughtful advice. He has many Ph.D.s and postdocs in his flock as well as many students who had him as an external examiner.

He has consistently served the Geomagnetism and Paleomagnetism (GP) community as reviewer, as associate editor, with service on U.S. National Science Foundation panels and AGU committees, and as president of our section.

It is appropriate that the GP section present this award to Dennis. He needs it to complete his collection of medals and awards. He won the Arthur L. Day Medal from the Geological Society of America in 2003. He’s a member of the National Academy. He’s got not one but two doctorates, and one of them is French! He got the the Vening Meinesz Medal from the University of Utrecht and the Petrus Peregrinus Medal from the European Geosciences Union. So to give this honor to Dennis is pretty much a no-brainer. I just hope he can find room on his mantelpiece for this one.

—Lisa Tauxe, University of California, San Diego, La Jolla

Thank you very much, Lisa, for your generous citation, and thank you, colleagues and friends, for being instrumental in the bestowal of this honor. This award is beautifully made, and the depiction of Gilbert’s terrella with the dipole axis laid horizontally is a wonderful reminder of the value of unorthodox perspectives in science. The GP section of AGU has been a great source of inspiration at all stages of my career by providing a forum for our discipline across the generations. I am grateful to all those “studious of the magnetic philosophy”—mentors, students, postdocs, and fellow researchers alike—who have provided such a collegial and stimulating context. Sustained collaborations with, to name a few, Neil Opdyke, Bill Lowrie, Steve Cande, Lisa Tauxe, Paul Olsen, Jeff Gee, and Giovanni Muttoni, ongoing joint work with great figures like Ted Irving, as well as further prospects of interactions with a new generation of thinkers and doers on the scene, have motivated and enriched my efforts in (continuing in the translated words of William Gilbert) “discovery of secret things and in the investigation of hidden causes…from sure experiments and demonstrated arguments” (not to mention lengthening my publication list!). I also gratefully acknowledge the more than 35 years of grant support from NSF and concurrent institutional support from Lamont and more recently Rutgers, and of course Carolyn on the home front, that provided the wherewithal to have such a good time doing research. Thank you all again, and be assured that the William Gilbert Award will have pride of place on my bookshelf. —Dennis Kent, Rutgers University, New Brunswick, N. J., and Lamont-Doherty Earth Observatory, Palisades, N. Y.