1993 ROBERT BERNER
Few scientists can be said to have invented or discovered an active field of research. Dr. Robert Berner, the sixteenth recipient of the A.G. Huntsman Award, is one of these rare individuals. His ideas on mathematical modelling of kinetics has transformed sedimentary geochemistry from an almost purely descriptive science to one of prediction and quantitative understanding. The focus of scientific writing in this area of science changed radically as a result of the publication of Dr. Berner's papers through the 1960s and 1970s. His two monographs on this subject (Principles of Chemical Sedimentology and Early Diagenesis: A Theoretical Approach) are the definitive texts on the subject, and the first is considered by many as a true classic of the geological literature. In his writings on sedimentary geochemistry he has argued that sediments are not mere repositories for chemicals, but are dynamic "reactors" that return transformed material to the oceans. (A sobering thought today, when man simply dumps massive amounts of human wastes and industrial effluents into coastal oceans, hoping that these will permanently settle there). As an experimental physical chemist he has established values of fundamental constants, such as the solubility of sulfide minerals, and he has introduced the first use of the now-ubiquitous pH-Stat in studying the kinetics of dissolution and precipitation of marine minerals. His "G-kinetics" for composition of organic matter are the most commonly used and tested models in sedimentary geochemistry. His efforts in paleoceanography have provided a quantitative way to distinguish between oxic and euxinic environments based on sulfur chemistry. More recently, Dr. Berner has extended his thinking about kinetic modelling to the coupling between geochemical cycles in the ocean and on land with the climate over geologic time. In conjunction with A.C. Lasaga and the late Bob Garrels, he illustrated how the long-term CO2 content of the atmosphere responds to oceanic processes, such as the removal of calcium and magnesium and the rate of sea-floor spreading. This work has been the basis for much of today's work on global geochemical climate.