THE BASINAL AND PALEOENVIRONMENTAL SETTING OF LATE EDIACARAN TAPHONOMIC WINDOWS IN THE SOUTHWEST USA

Latest Ediacaran fossils, including tubular body fossils and erniettomorphs, have been discovered within multiple stratigraphic intervals at six localities in southern California and Nevada. The fossils are variably preserved in four distinct taphonomic windows: as pyrite pseudomorphs, casts and molds, carbonaceous compressions, and calcified tubes. Using sequence stratigraphy, sedimentology, and carbon isotope chemostratigraphy from over a dozen sections, we refine correlations between Ediacaran-Cambrian boundary sections in the White-Inyo, Esmeralda County, and Death Valley regions and place these body fossils into a spatial, temporal, and paleoenvironmental context within the basin. This multi-disciplinary dataset provides new insights into the nature of latest Ediacaran environmental and biological transitions in southwestern Laurentia, and builds the regional framework necessary to examine the specific controls on taphonomic windows that produce exceptional Ediacaran fossil preservation.