Early Eocene to middle Miocene cooling and aridification of East Antarctica

摘要: [1] Few high-latitude terrestrial records document the timing and nature of Cenozoic “Greenhouse” to “Icehouse” transition. Here we exploit bulk geochemistry marine siliciclastic sediments from drill cores on Antarctica's continental margin extract a unique semiquantitative temperature precipitation record for Eocene mid-Miocene (~54–13 Ma). Alkaline elements are strongly enriched in detrital mineral fraction fine-grained only occur as trace metals biogenic fraction. Hence, climofunctions similar chemical index alteration (CIA) can be applied alkaline major element margins order reconstruct changes temperature. We validate this approach by comparison with published paleotemperature derived fossil wood, leaves, pollen find remarkable agreement, despite uncertainties calibrations different proxies. A long-term cooling ?8°C is observed between Early Climatic Optimum (~54–52 Ma) middle Miocene (~15–13 onset transient episodes at ~46–45 Ma. High-latitude stratigraphic currently exhibit insufficient temporal resolution aridity inferred ice-sheet development during late (~45–37 However, an abrupt aridification East Antarctica near Eocene-Oligocene transition (~34 Ma), which suggests that ice coverage influenced atmospheric circulation patterns through albedo effects earliest Oligocene onward.