We report semiquantitative elemental data from X-ray fluorescence (XRF) scanning of Site U1558 sediment cores drilled during International Ocean Discovery Program Expeditions 390C and 393. These expeditions, together with Expeditions 395E and 390, form the South Atlantic Transect, which collected sediment and basement cores from the western flank of the southern Mid-Atlantic Ridge. XRF scanning of the continuous splice of Site U1558, using Holes U1558A and U1558F, was conducted at three acceleration voltages to capture a range of major, minor, and trace elements. At Site U1558, positive correlations exist between terrigenous-sourced elements (Al, Si, Ti, and Fe) and a negative correlation exists between the terrigenous-sourced elements and Ca. XRF geochemistry is correlated with lithologic changes, most notably at the boundary of Lithologic Units I and II, where Unit I is brown and reddish brown nannofossil-rich clay and Unit II is pink, pinkish white, pinkish gray, and light brown nannofossil ooze and chalk with varying amounts of clay and foraminifera. Peaks in XRF data align with the boundaries of Lithologic Subunits IIA and IIB and Subunits IIB and IIC. 
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                            Data report: X-ray fluorescence scanning of sediment cores, IODP Expedition 390/393 Site U1557, South Atlantic Transect
                        
                    
    
            Site U1557 is the deepest and one of the oldest sites drilled during International Ocean Discovery Program Expeditions 390C, 395E, 390, and 393 on the South Atlantic Transect. It differs from the nearby Site U1556, which also sits on early Paleocene crust, by its stratigraphically expanded Paleocene–Eocene section. Here, we present the results of programmatic X-ray fluorescence (XRF) core scanning of the entire thickness of the sedimentary section at Site U1557. We find a major shift in XRF geochemistry at the boundary between Lithologic Units I and II, coincident with a shift in spectral gamma ray and magnetic susceptibility, as well as a shift from alternating pelagic carbonate and pelagic clay in Unit I to pelagic carbonate in Unit II. Within Unit I, shifts in major elemental composition of core material track alternations between carbonate-rich and clay-rich intervals. 
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                            - Award ID(s):
- 1326927
- PAR ID:
- 10500169
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- International Ocean Discovery Program
- Date Published:
- Journal Name:
- Proceedings of the International Ocean Discovery Program Expedition reports
- Volume:
- 390/393
- Issue:
- 201
- ISSN:
- 2377-3189
- Subject(s) / Keyword(s):
- International Ocean Discovery Program IODP JOIDES Resolution Expedition 390 Expedition 393 Expedition 390C Expedition 395E South Atlantic Transect South Atlantic Ocean Atlantic Ocean Site U1557 X-ray fluorescence core scanning XRF core scanning Paleocene Eocene Oligocene Miocene Pliocene Pleistocene
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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