{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,1,21]],"date-time":"2025-01-21T05:08:59Z","timestamp":1737436139901,"version":"3.33.0"},"posted":{"date-parts":[[2025,1,20]]},"group-title":"oral","reference-count":0,"publisher":"Copernicus GmbH","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>Although valuable information of North Atlantic circulation paleo-reconstructions by the measurement of oxygen isotopes of benthic and planktonic foraminifera exists, it is still not well-understood how deep-water currents changed over the last ~800,000 years. Moreover, recent studies have shown that some species of microfossils can adapt to low oxygen concentrations, which consequently can impact the reliability of the paleo-reconstructions that are based on these fossils. Marine sediments off the Portuguese Margin have been shown to play a pivotal role in paleoclimate research, and studies have suggested that climate shifts at Mediterranean latitudes are interconnected to changes in deep-water circulation patterns. Changes in bottom-water oxygenation (ventilation) can provide information about changes in deep-water circulation patterns, which can be measured by the enrichment versus depletion of redox-sensitive trace metals. Here we provide the results of a low-resolution geochemical analysis of redox-sensitive trace metals (for example, molybdenum (Mo), vanadium (V), and uranium (U)) to investigate deep-water ventilation changes in the North Atlantic over the last ~800,000 years at Hole U1586A drilled during IODP Expedition 397. Sediment samples underwent a multi-acid digestion technique and were analyzed via an Inductively Coupled Plasma Mass Spectrometry (ICP-MS) for redox-sensitive trace metals. Additionally, sequential iron (Fe) extractions were carried out to differentiate between labile versus mineral Fe phases. Preliminary results suggest minor changes in deep-water ventilation that correspond to glacial-interglacial cycles since the mid-Pleistocene. Future work will involve high-resolution geochemical analyses to better understand the interconnection of deep-water circulation and climate change.<\/jats:p>","DOI":"10.5194\/egusphere-egu24-6679","type":"posted-content","created":{"date-parts":[[2024,3,8]],"date-time":"2024-03-08T15:42:09Z","timestamp":1709912529000},"source":"Crossref","is-referenced-by-count":0,"title":["Investigating North Atlantic Deep-Water Ventilation Changes: Preliminary Results from IODP Expedition 397 Hole U1586A"],"prefix":"10.5194","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4060-0700","authenticated-orcid":false,"given":"Lauren","family":"Haygood","sequence":"first","affiliation":[]},{"given":"Natascha","family":"Riedinger","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8537-1588","authenticated-orcid":false,"given":"David","family":"Hodell","sequence":"additional","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9110-0212","authenticated-orcid":false,"given":"Fatima","family":"Abrantes","sequence":"additional","affiliation":[]},{"given":"Carlos","family":"Alvarez Zarikian","sequence":"additional","affiliation":[]},{"name":"Expedition 397 Scientific Party","sequence":"additional","affiliation":[]}],"member":"3145","container-title":[],"original-title":[],"deposited":{"date-parts":[[2025,1,20]],"date-time":"2025-01-20T10:50:42Z","timestamp":1737370242000},"score":1,"resource":{"primary":{"URL":"https:\/\/meetingorganizer.copernicus.org\/EGU24\/EGU24-6679.html"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,1,20]]},"references-count":0,"URL":"https:\/\/doi.org\/10.5194\/egusphere-egu24-6679","relation":{},"subject":[],"published":{"date-parts":[[2025,1,20]]},"subtype":"other"}}