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During November 2011, Integrated Ocean Drilling Program (IODP) Expedition 339 departed from Ponta-Delgada/Azores, Portugal, with the main purpose of drilling in the Gulf of Cádiz to investigate tectonic and climatic control on the evolution of the Mediterranean Outflow. Furthermore, Site U1385 (Shackleton site) drilled off the southwest Portuguese margin, was expected to provide the possibility to extend back to the Pliocene, the bipolar record recognized in the area by Shackleton et al. (2000). At the end of the expedition, another core was drilled at about the same latitude as Site U1385 but closer to the coast, Site U1391 (see the “Expedition 339 summary” chapter [Expedition 339 Scientists, 2013]).

The Portuguese margin’s location makes it an important spot to investigate the impact of global climate conditions on the regional processes, be it primary production resulting from the coastal upwelling conditions generated by the Iberian-Canary upwelling system; the surface, intermediate, and bottom water strength and chemical characteristics; or ecosystem behavior. To do so, in particular to allow for intercore and global comparison of the many proxy data being produced, it is basic that the respective site’s splice is as precise as possible and that an accurate age model can be established. The Site U1385 splice was improved on the basis of the X-ray fluorescence (XRF) data, and its age model, mainly based on the benthic foraminifer oxygen isotope record, has been an object of extensive verification (Hodell et al., 2015). In order to improve the splice definition and age model for Site U1391, we have run XRF analysis on cores from Holes U1391A and U1391B between 76.51 and 205.77 meters below seafloor (mbsf) (81.47–235.53 meters composite depth [mcd]). This manuscript reports on the correction applied to the shipboard Site U1391 splice based on XRF data. Furthermore, it presents a preliminary age model defined through the correlation to the well-dated Site U1385 log(Ca/Ti) record.