This project involves experimental studies of the effects of chemical environments on crack propagation in geological materials. The project will extend previous studies on quartz crystals and will initiate new experiments on other minerals (including potassium feldspar, amphibole, muscovite mica, and gypsum) and on polycrystalline rock samples (granite, sandstone, and marble). Crack propagation experiments will use a constant- moment double cantilever beam apparatus and will involve a variety of chemical surfactants chosen specifically to elucidate the mechanisms of hydrolytic weakening. The results of these experiments will increase our understanding of the processes of crack propagation in natural materials and of the important role of aqueous fluids in these processes.
