9614149 Leger The P.I.s propose an experimental study of the dynamics of coupled mechanical and chemical processes that occur during the deformation and diagenesis of sediments under hydrothermal conditions. During this award period, the P. I.'s will begin experimentation on a system more typical of that which occurs in natural sedimentary basins. A sand with the composition of a 2-feldspar granite will be deformed under hydrothermal conditions with a pore fluid of aqueous brine with a composition typical of that found in sedimentary basins. The hot fluid will be continuously circulated through the sample and permeability measured as a function of time in order to study the precipitation sealing mechanism discovered in our their work. Both closed and open fluid systems will be studied. The pore fluids will be sampled periodically to monitor its chemical evolution. The post-experimental material will be studied to determine the dissolution and precipitation mechanisms, species and their localization. ***
