| Summary: | Superimposed on the warm greenhouse climate of the early Paleogene, several hyperthermals, warming events with a duration of ca. 200 kyr or even shorter, were observed. Of these, the Paleocene-Eocene Thermal Maximum (PETM; ca. 56 Ma) is the most extreme and best studied example. During the PETM, the injection of isotopically light carbon into the ocean/atmosphere system resulted in a >2 ‰ negative carbon isotope excursion (CIE), a temperature rise of up to 5°C, an extinction among benthic foraminifera and evolutionary innovations among other lineages. The Latest Danian Event (LDE or Top Chron 27n Event; 61.75 Ma) is characterized by a >1 ‰ negative benthic foraminiferal CIE in various sections in Egypt, which has been correlated to carbon isotope shifts of ~0.7 ‰ in Zumaia (Spain), Wombat Plateau (ODP 761B, Indian Ocean) and Shatsky Rise (ODP 1209, Pacific Ocean) (Bornemann et al., 2009; Westerhold et al., 2011). Westerhold et al. (2011) calculated a distinct 2°C bottom water temperature rise during this event at ODP Site 1209 (Shatsky Rise), suggesting a hyperthermal nature for this event. At the onset of the LDE, absence of benthic fauna, enrichment in redox-sensitive trace elements and lamination demonstrate the development of anoxic conditions on the Egyptian shelf. The onset of the LDE coincides with a sequence boundary. As the sea-floor oxygenation improves, an opportunistic inner-middle neritic Neoeponides duwi assemblage occurs, after which the outer neritic-bathyal benthic fauna recovered (Schulte et al., 2013). Clyde et al. (2010) showed that the Asian Shanghuan-Nongshanian and the North American Torrejonian- Tiffanian land mammal age boundaries might correspond to the LDE. Studies on calcareous nannoplankton show that the LDE coincides with the first radiation of fasciculith calcareous nannofossils, and relative abundance changes suggest warmer sea surface waters and more eutrophic conditions (Monechi et al., 2013). Deep-sea benthic foraminiferal assemblages have not been studied so far. This presentation will show the first results of benthic foraminiferal faunal and isotopic patterns related to the LDE at Walvis Ridge (ODP Site 1262, Southern Atlantic Ocean, paleodepth ca. 3000 m). The percentage of planktonic foraminifera is ca. 99.5 % before and during the early part of the event, lowering to ca. 99.0 % during the second part. This indicates good carbonate preservation throughout the section. status: published
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