BrGDGT-based temperature evolution through an Eocene hyperthermal event

Branched glycerol dialkyl glycerol tetraethers (brGDGTs) from maar sediments were analyzed in order to reconstruct continental air temperatures across a middle Eocene (47.2 Ma) hyperthermal event. Additionally, carbon isotopes of total organic carbon (δ13C TOC) were measured from the same samples to reconstruct changes in global and local carbon cycle. Measurements for both, brGDGTs and carbon isotopes, were carried out between beginning of 2021 and end of 2022. Based on the current age model the temporal resolution of the samples is millennial to sub-millennial. Sediment samples (organic-rich pelites) are from the FB2001 drill core, recovered from the Messel Fossil Site located in the vicinity of Frankfurt, Germany. The brGDGTs were solvent extracted by Soxhlet apparatus and further analyzed by high-performance liquid chromatography (HPLC-) - atmospheric pressure chemical ionization (APLCI-) - mass spectrometry (MS). Aliquots for total organic carbon isotope measurements were decalcified with HCl (10%) prior analyses on a Flash Elemental Analyzer.