EVALUATING CHANGE AT THE BONNEVILLE SALT FLATS, UTAH

Recent changes in surface properties of the Bonneville Salt Flats (BSF) have led to concerns about land use sustainability and potash mining mitigation efforts. Ongoing interdisciplinary research seeks to characterize modern surface processes, landscape changes, and associated environmental properties that impact this dynamic salt pan. In the Fall of 2016, sixty-nine shallow (up to ~2m deep) sediment cores were drilled and collected to characterize the sedimentary architecture of BSF. These cores provide new detailed data about the spatial heterogeneity in the composition of the saline strata that caps the larger regional Bonneville basin lacustrine deposits. The BSF saline facies include surface bedded halite, subsurface course porous halite, and range of interbedded gypsum sand units that generally fine upwards. The subsurface saline sediments are heavily impacted by diagenetic processes including displacive halite growth, halite dissolution, and the formation of biofilms. Sedimentary texture, mineralogy, and geochemistry of the cored strata are evaluated to assist in regional correlation and interpretation of processes impacting the sediments. In addition, these new subsurface data allow for comparisons with historic measurements of the BSF strata that have been made on decadal time scales since 1960. Evaluation of changes in sedimentary architecture through time help to constrain the processes that are impacting the landscape.