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This report presents the X-ray fluorescence (XRF) data generated by scanning sediment cores from International Ocean Discovery Program (IODP) Expedition 401 Site U1611 in the Alborán Sea as part of the Investigating Miocene Mediterranean–Atlantic Gateway Exchange (IMMAGE) Land-2-Sea drilling project. The main goal of Expedition 401 was to investigate the paleoclimate and paleoceanographic impact of changes in the Mediterranean–Atlantic gateway during the Late Miocene. Site U1611 is located on the eastern side of the Gibraltar Strait, the present-day gateway. The recovered succession is a nearly continuous record of sediment before, during, and after the formation of a salt giant in the Mediterranean, the Messinian Salinity Crisis (MSC; 5.33–5.97 Ma). XRF scanning of these sediment cores at very high resolution (ranging 2 mm to 5 cm) produces semiquantitative elemental abundance data providing geochemical information about paleoceanographic changes through time. These data show moderate positive correlation between terrigenous elements (e.g., Al strongly positively correlated to Si and Ti) and weak negative correlations between terrigenous and biogenic elements. In contrast with the well-developed orbital cyclicity visible in many Late Miocene Mediterranean successions, the XRF data from these cores lack obvious cyclicity. This is likely due to the Alborán Basin's complicated depositional environment, which consists of a mixture of gravity flows and thinly laminated pelagic/hemipelagic sediments. These new data provide additional evidence that permits the reconstruction of Late Miocene paleoceanographic conditions in the Alborán Basin.
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This content will become publicly available on January 21, 2027
Data report: X-ray fluorescence scanning of sediment cores, IODP Expedition 401 Site U1385, southwest Iberian margin (Portugal)
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.
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- Award ID(s):
- 2412279
- PAR ID:
- 10660450
- Publisher / Repository:
- International Ocean Discovery Program
- Date Published:
- Volume:
- 401
- Issue:
- 202
- ISSN:
- 2377-3189
- ISBN:
- 978-1-954252-94-3
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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