INTRODUCTION

This special triple issue of the American Journal of Science is offered as a tribute tothe career of Robert A. Berner. The timing of this issue coincides with no specialevent—Bob’s retirement is still some time away. Rather, Bob’s work has become soprominent in shaping our thinking on the controls on geochemical processes and theirconsequences to the cycling of biologically-active elements that, quite simply, ‘‘the timeis right.’’ Over the years Bob’s seminal contributions have indelibly molded numerousareas of low-temperature geochemistry including: the study and modeling of earlydiagenesis, the kinetics of Earth surface chemical processes including chemical weather-ing, the biogeochemistries of carbon, sulfur, and phosphorus, and their regulation overgeologic time. The present issue was conceived in the spirit of these contributions. Wegreatfully thank Marie Casey of AJS for her help in making this issue become reality.

Bob is currently the Alan M. Bateman Professor of Geology and Geophysics at YaleUniversity. He completed his undergraduate studies at the University of Michigan andhis Ph.D. at Harvard University, under the direction of Raymond Siever (but also withguidance from Bob Garrels). Bob Berner has been the recipient of numerous of awards,including Membership in the National Academy of Sciences (1987), Doctor HonorisCausa from the Universite Aix-Marseille (France) in 1991, the Huntsman Medal inOceanography (Canada) in 1993, the Goldschmidt Medal (Geochemical Society) in1995, the Arthur L. Day Medal (Geological Society of America) in 1996, and theMurchinson Medal (Geological Society-London) in 1996. A truly accomplished andrecognized career!

The eleven papers in this triple issue were invited, and both with respect toauthorship and content each bears a strong relationship to Bob and his work. The firstfour papers highlight recent advances in our understanding of early sediment diagenesisand its modeling. The paper by Boudreau and Bennett applies new concepts incompaction theory to develop a new porosity equation for application in early diageneticmodeling. The paper by Hedges and others provides new insights into the processescontrolling organic matter preservation in sediments, while the paper by Hurtgen andothers discusses how iron sulfide enrichment may occur in sediments underlying euxinicmarine water columns; this may be a process quite common to euxinic basins. The paperby Martens, Albert, and Alperin discusses the use of stable isotopes to trace the processof anaerobic methane oxidation in active marine sediments.

The next three papers discuss the processes of chemical weathering on time scalesranging from that in the laboratory to that of the geological record. The paper by Gibbsand others discusses and quantifies the factors influencing chemical erosion on a globalscale over the last 250 my. Luttge, Bolton, and Lasaga use a new interferometrictechnique to study the regulation of anorthite dissolution kinetics, while Velbel illustratesthe influence of bond strength on the relative weathering rates of simple orthosilicateminerals.

The final four papers deal with the biogeochemical cycling of elements over a broadrange of time scales. The paper by Canfield and Raiswell describes the biological andchemical evolution of the sulfur cycle over geologic time. Clark, Ingall, and Bennerutilize nuclear magnetic resonance to unravel important aspects of organic phosphoruscycling in the marine realm. Morse and Marion take us beyond the Earth environmentand discuss carbonate-mineral buffering of the chemistry of possible early oceans onMars. Finally, Ver, Mackenzie, and Lerman consider the cycling of nutrients and carbonover the last 300 yrs and man’s recent impact on biogeochemical cycling in order topredict the nature and magnitude of nutrient cycling in the future.

Six of the contributors are Bob’s former students (Boudreau, Canfield, Ingall, Lyons,Morse, and Velbel), one is a former post-doctoral student (Martens), and two others arecolleagues with whom Bob has published extensively (Raiswell and Lasaga). One ofBob’s principal scientific mentors was the late Bob Garrels, and it is particularly fitting

v

that one of the contributors (Kump) was a former student of Bob Garrels, while twoothers were Bob Garrels’ close colleagues (Mackenzie and Lerman). The remainingcontributors are students and good colleagues who have been significantly influenced byBob’s work. As a measure of his influence and popularity, we were approached bynumerous scientists eager to contribute to this special issue. Unfortunately, spacelimitations prevented their participation, although Bob will surely appreciate theirinterest.

We also wish to highlight another aspect of Bob’s career: that is his exemplary roleas a mentor and a friend. While working in Bob’s laboratory we felt very much theweight of his accomplishments and the accomplishments of those who had preceded us.This was a challenge and encouraged us to perform to the limits of our abilities. Bob hasalways taken a strong personal interest in his students and postdocs. At least in our time,Friday happy hour at various watering holes (such as The New England House, TheWinery, or Malones) was a faithfully-attended ritual. After several entertaining storiesabout such legendary characters as The Pharaoh, Uncle Humpherey and Aunt Esther, orthe Arbuckle Family (the ‘‘A’’ in R.A., which, Bob stressed, did not include ‘‘Fatty’’) oralternatively tales of the BBSAC (Bermuda Biological Station Athletic Club), it was alsoritual for Bob to pick up the bill for the students. And, we were often invited to enjoy thehospitality of Betty and Bob in their home. Bob would try to teach us about fine wine,entertain us with more stories, and if the mood was right, he would treat us to one of hisnewly-written piano sonatas. A big party always accompanied a thesis defense. How-ever, before the real party began a quiet dinner was arranged with Betty, Bob, and newPh.D candidate, and a guest. Bob would traditionally serve a select wine from his cellarand usually far beyond the sophistication of the successful candidate but fully appreci-ated as special.

With loving admiration we offer this special issue of the American Journal ofScience to you, Bob.

Don and Bernie

Donald CaufieldOdense, Denmark

Bernard BoudreauHalifax, Nova Scotia, Canada

Introductionvi

Robert A. Berner, Bateman Professor of Geologyat Yale University, at the time of the award of theHunstman Medal. (Courtesy of K. Bentham, Bed-ford Institute of Oceanography.)

Bob in the field in Hawaii studying thepractical effects of weathering.

Bob after his receipt of the Goldschmidt Medal, pictured with his wife Betty and his first student, John Morse.

iii