INTEGRATED CHEMOSTRATIGRAPHY, GEOCHRONOLOGY, AND PALEONTOLOGY OF EDIACARAN DEPOSITS FROM THE CARIBOO MOUNTAINS, BRITISH COLUMBIA, CANADA

Ediacaran strata (635-539 Ma) record the early appearance and diversification of animal life in the fossil record. Ediacaran fossils are widespread in stratigraphic successions around the globe, and contain notable developmental and ecological changes along with potentially extreme perturbations to global climate. Ultimately, numerous studies have attempted to explain these evolutionary transitions and environmental changes as drivers for the initial rise of Ediacaran diversity and eventual extinction at the Precambrian-Cambrian boundary. However, such inferences rely on correct recognition of correlative strata between different successions to rigorously compare environmental change with accurate measures of diversity in the fossil record. Unfortunately, it is known that taphonomic biases limit the biostratigraphic utility of Ediacaran organisms, leaving only chemostratigraphic and geochronometric data to correlate units. In this study, we present new lithostratigraphic, paleontological, carbon isotope chemostratigraphic (d¹³C_carb), and geochronological data from Ediacaran mixed carbonate-siliciclastic slope and platformal Ediacaran-aged rocks of the Windermere Supergroup in the Cariboo Mountains, B.C., Canada. These data enable us to establish new correlations for formations within the Cariboo Group (Isaac, Cunningham, Yankee Belle, Yanks Peak) and compare the location of the Ediacaran-Cambrian boundary in the Cariboo Mountains to Windermere Supergroup strata preserved elsewhere in the Canadian Cordillera. Lastly, our carbon isotope data build upon recent studies to provide important context for the global Ediacaran carbon cycle.