Mineral/water interactions close to equilibrium

The second Karlsruhe Geochemical Workshop is dedicated to the improved understanding of water/solid interactions and, in particular, dissolution/precipitation reactions at the close to equilibrium conditions typical of natural systems. This topic is of widespread interest at present because these reactions are fundamental to a large number of geochemical processes at both low and high temperatures. For example, at the surface of the earth the dissolution and precipitation of carbonate minerals contribute significantly to the CO_2 content of the atmosphere, and thereby effect climate. Another fundamental topic involves long term stability of radioactive waste contained within glass in the near-subsurface because the stability is controlled by the dissolution rates of these glasses. The porosity and permeability of petroleum reservoirs is intimately linked to the precipitation of quartz cements and clay minerals, respectively, at close to equilibrium conditions. At elevated temperatures, the deposition of hydrothermal ore deposits is the result of precipitation and dissolution reactions among fluids circulating in fractures and their host rocks. Over the past several years we have been witnesses to a dramatic increase in our understanding of processes that occur at the solid-water interface. This is, in large, partly due to the application of new and/or improved experimental techniques. Many of these techniques are detailed in this proceedings volume including: flow-through hydrothermal reactors that allow the measurement of dissolution and precipitation rates at independently controlled solution compositions, use of synchrotron radiation sources that enable in-situ identification of the species at mineral surfaces in the presence of reacting solutions, and atomic force microscopy which permits in-situ characterization of surface structures while fluid-mineral surface reactions occur. (orig.)Available from TIB Hannover: ZA 5141(6291) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman