Stable isotope and minor element proxies for Eocene climate of Seymour Island, Antarctica

[1] Abundant and well-preserved marine macrofossils on Seymour Island, Antarctica, provide a valuable resource to establish paleoenvironmental conditions at high southern latitudes during the warm Paleogene. Stable isotope, minor element, and Sr/Sr compositions have been measured for the aragonite bivalve Cucullaea from the Eocene La Meseta Formation. The Sr/Sr stratigraphy suggests an early to late Eocene age for the La Meseta Formation. Sea surface temperature estimates based on dO values range from 14.5 to 15.5 C in the early and middle Eocene to 10.5 C in the late Eocene. High-resolution sampling along growth structures provides estimates of seasonality in temperature, which decrease considerably up section. To address the relative contribution of temperature and ice volume or salinity to the dO record, Sr/Ca was measured and evaluated as a potential independent paleothermometer for Cucullaea.