The diagenesis of deeply buried quartz arenite sandstones is important in the evolution of sedimentary basins, including paleohydrology and thermal history and the transition from high grade diagenesis to low grade matamorphism. The primary aim of petrographic study will be to measure quantitatively cementation by quartz and carbonate, pressure solution (geometry of grain contacts, timing and extent of chemical compaction), and porosity loss as a function of pressure, temperature and integrated time- temperature history. Samples will be examined by petrographic microscopy, cathodo-luminescence and SEM, as well as by some chemical and istotopic analyses. The diagenetic history will be reconstructed and set in the context of burial and thermal history. Pressure solution will be one of the main focuses, especially as it pertains to the transition between the high grade diagenesis of deep burial and the low grade metamorphism of parts of deformed mountain belts. Sandstones to be sampled include the Pennsylvanian of the Green River basin, Pennsylvanian and Ordovician of the Anadarko basin, and Cambrian of the Michigan and Illinois basins. Now uplifted undeformed and deformed sections of the Pennsylvanian of Pennsylvania will be compared with the Rhode Island Pennsylvanian and the Silurian Clough quartzite of New Hampshire. The oldest sandstones will be of Proterozoic quartz arenites from a well-studied section of Spitsbergen. This study has practical significance in the loss of porosity of quartz arenites at great depths (4-9km), which influences the mass transfer of fluids and thus production of oil and, especially, gas.
