The PhD researcher will contribute to the goals of PASSAGE using a combination of biogeochemical techniques, such as implementation of age-depth models, biomarker quantification and isolation, geochemical characterization of sedimentary particles, and implementation of isotope mixing models and correction of existing records. The PhD researcher will conduct original primary research that will conclude with the production of an original PhD thesis. The PhD researcher will be based at University of Salamanca and enrol the Oceanic Geosciences research group (https://oceano.usal.es/en/bienvenidos/), which holds extensive expertise in both Oceanography (water-column, sediment traps, and surface sediments) and Paleoclimate studies (climate variability at different time scales). The PhD researcher will benefit from further continuing education, which includes experience and laboratory skills in sampling and both well-established and novel methods in the (paleo)oceanographic field(s), research stays at other field-leading European institutions (e.g., ETH Zurich (Switzerland) and IPMA (Portugal)), and active participation in oceanographic cruises, workshops, and conferences. The PhD researcher is also given the opportunity to gain teaching experience if language and academic background allow.