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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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This content will become publicly available on February 12, 2027
Data report: X-ray fluorescence scanning of sediment cores, IODP Expedition 401 Site U1610, Gulf of Cádiz, Atlantic
International Ocean Discovery Program (IODP) Expedition 401 recovered sediment cores from Site U1610, located in the Gulf of Cádiz. This report presents semiquantitative chemical results based on high-resolution (5 cm) X-ray fluorescence (XRF) scanning of Hole U1610A Miocene to Pliocene core sections from 4.5 to 6 Ma (651–1026 m core depth below seafloor, Method A [CSF-A]). Processed element intensities (counts per second) of Al, Si, Ti, Fe, Rb, Ca, Sr, Zr, Mn, and Ba are discussed. XRF results are divided into four units with depth according to the amplitude and wavelength of cyclicities, among which clear cyclicities with 4–7 m wavelengths are observed in Unit 1. Unit 3 and the upper part of Unit 4 (middle Messinian Salinity Crisis [MSC]) have higher amplitude cyclicity, and Unit 2 (close to the Miocene/Pliocene boundary) and the lower part of Unit 4 (early MSC) have the lowest amplitude signals. The most pronounced spikes of XRF and physical properties occur in the middle of the MSC and at the onset of the MSC. Additionally, this report discusses the implications regarding terrigenous versus biogenic components. There are positive correlations between terrigenous elements (Al, Si, and Ti), but generally weak negative correlations dominate between these terrigenous elements and biogenic elements (Ca and Sr). This high-resolution data set, in conjunction with other data sets produced from Expedition 401, will help with the interpretation of the sedimentary processes and paleoclimate changes impacting the Gulf of Cádiz before, during, and after the MSC.
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- Award ID(s):
- 2412279
- PAR ID:
- 10665428
- Publisher / Repository:
- International Ocean Discovery Program
- Date Published:
- Journal Name:
- Proceedings of the International Ocean Discovery Program Expedition reports
- Volume:
- 401
- Issue:
- 203
- ISSN:
- 2377-3189
- ISBN:
- 978-1-954252-94-3
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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