Six of the nation's most outstanding geochemists and petrologists convened May 6, 1988, to honor the late Hans P. Eugster at a symposium organized by the Department of Earth and Planetary Sciences, The Johns Hopkins University, Baltimore, Md. (see photo). Over 100 of Hans' collegues, students, and friends gathered to pay tribute both to a man they fondly remebered and to the lesson offered by his scientific career—that profound discoveries follow from the application of fundamental chemical principles to geological processes. The hour-long presentations were a good mix of current research and reminiscences about the development of now time-honored practices in goechemistry.
Harold C. Helgeson (Department of Geology and Geophysics, University of California at Berkeley) intrigued the symposium with his vision of future developments in theoretical organic geochemistry. He outlined how equations of state for inorganic aqueous electrolyte solutions may be extended to dissolved aqueous organic species. Already, these new developments enable a quantitative analysis of goechemical processes that invlove both inorganic and organic species in solution. Examples include the generation and maintenance of the oxidation states of oil-field brines, the migration and accumulation of petroleum, and abiologic processes involving hydrothermal fluids in the origin of life. He suggested that redox reactions involving acetate may control hydrothermal transport and precipitation of petroleum in sedimentary basins. Oil accumulations, Helgeson speculated, could be regarded as just another kind of hydrothermal “ore deposit.”