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Following International Ocean Discovery Program (IODP) Expedition 397, split archive halves from Site 397-U1385 were analyzed at 1 cm resolution using an Avaatech X-ray fluorescence (XRF) core scanner at the University of Cambridge (United Kingdom). The resulting Ca/Ti profiles were used to revise the composite depth scales of Integrated Ocean Drilling Program Sites 339-U1385 and 397-U1385. Expedition 339 recovered a nearly continuous sediment sequence to 151.5 meters below seafloor (mbsf) at Site U1385, except for a gap spanning Marine Isotope Stage (MIS) 11/Termination V at 53.06 mbsf. This interval was successfully retrieved during Expedition 397, completing the 1.45 My section. The existing depth scale for Site 339-U1385 was revised to integrate this missing sequence. Using dynamic programming, the Ca/Ti signal from Site 397-U1385 was stretched and compressed to align with the revised depth scale of Site 339-U1385. This alignment enables direct transfer of age models and isotopic records between the two. Below 1.45 Ma (148.83 m core depth below seafloor, Method A [CSF-A], or 176.64 m core composite depth below seafloor [CCSF]), the chronology at Site 397-U1385 is established through benthic oxygen isotope stratigraphy and orbital tuning. The isotope record aligns with Site 339-U1385 for MISs 41–47 and extends to MIS 61, where a hiatus (~1.72–1.87 Ma) removed MISs 62–70. Below the hiatus, pronounced precession-driven variations in Ca/Ti serve as the basis for astronomical tuning, extending the chronology to 5.3 Ma. The Site 397-U1385 record provides a near-continuous record of changes in sediment composition at millennial resolution to the base of the Pliocene. 

The North Atlantic and Arctic Oceans are unquestionably major players in the climatic evolution of the Northern Hemisphere and in the history of the Northern Hemisphere overturning circulation of the Atlantic Ocean. The establishment of the modern North Atlantic Water (NAW) transporting heat, salt, and moisture to the Northern Hemisphere has been indicated as one of the main forcing mechanisms for the onset of Northern Hemisphere glaciation. NAW controls the extent and dynamics of circum-Arctic and circum-North Atlantic ice sheets and sea ice in addition to deep water and brine production. How the ocean system and cryosphere worked during past warmer intervals of high insulation and/or high atmospheric CO2 content is still largely unknown and debated. The required information can only be attained by offshore scientific drilling in high-resolution continuous expanded sedimentary sequences identified on the western continental margin of Svalbard and eastern side of the Fram Strait, along the main pathway and northern penetration of the NAW flowing into the Arctic Ocean. The area around Svalbard is very sensitive to climatic variability and can be considered a sentinel of climate change. Furthermore, the reconstruction of the dynamic history of the marine-based paleo-Svalbard–Barents Sea Ice Sheet is important because it is considered the best available analog to the modern, marine-based West Antarctic Ice Sheet, for which the loss of stability is presently the major uncertainty in projecting future global sea level rise in response to the present global climate warming. 

The North Atlantic and Arctic Oceans are unquestionably major players in the climatic evolution of the Northern Hemisphere and in the history of the Northern Hemisphere overturning circulation of the Atlantic Ocean. The establishment of the modern North Atlantic Water (NAW) transporting heat, salt, and moisture to the Northern Hemisphere has been indicated as one of the main forcing mechanisms for the onset of Northern Hemisphere glaciation. NAW controls the extent and dynamics of circum-Arctic and circum-North Atlantic ice sheets and sea ice in addition to deep water and brine production. How the ocean system and cryosphere worked during past warmer intervals of high insulation and/or high atmospheric CO2 content is still largely unknown and debated. The required information can only be attained by offshore scientific drilling in high-resolution continuous expanded sedimentary sequences identified on the western continental margin of Svalbard and eastern side of the Fram Strait, along the main pathway and northern penetration of the NAW flowing into the Arctic Ocean. The area around Svalbard is very sensitive to climatic variability and can be considered a sentinel of climate change. Furthermore, the reconstruction of the dynamic history of the marine-based paleo-Svalbard–Barents Sea Ice Sheet is important because it is considered the best available analog to the modern, marine-based West Antarctic Ice Sheet, for which the loss of stability is presently the major uncertainty in projecting future global sea level rise in response to the present global climate warming. 

This report presents the results of X-ray fluorescence (XRF) scanning of sediment cores from International Ocean Discovery Program (IODP) Expedition 401 Site U1385, conducted as part of the Investigating Miocene Mediterranean–Atlantic Gateway Exchange (IMMAGE) Land-2-Sea drilling project. The expedition investigated Atlantic–Mediterranean exchange during the Late Miocene, focusing on the Messinian Salinity Crisis and its impact on climate and oceanography. Site U1385 is located on the Promontório dos Principes de Avis, a promontory extending west from the Portuguese margin in the northeast Atlantic, and recovered sediments from the lowermost Pliocene to the Tortonian. XRF scanning provides semiquantitative elemental data at a 2 cm resolution, revealing cyclic patterns in elemental abundances that reflect lithologies and can be correlated cyclostratigraphically with orbital cycles. These data highlight strong positive correlations among terrigenous elements (Al, Si, Ti, Mn, and Ba) and negative correlations between terrigenous and biogenic (Ca and Sr) elements. These results contribute to understanding the paleoceanographic and paleoenvironmental conditions at Site U1385 during the Upper Miocene and Lower Pliocene, providing insights into sediment provenance, diagenetic processes, and climatic variations.