5:15 PM - 7:15 PM
[MIS14-P08] Decadal-scale paleoceanographic fluctuations in the Japan Sea during the late Miocene: A preliminary report from LA-ICP-MS–based quantitative in situ chemical analyses
★Invited Papers
Keywords:LA-ICP-MS, Japan Sea, Late Miocene, Redox sensitive elements, IODP Exp. 346, Repository Core Re-Discovery Program (ReCoRD)
The paleoceanographic environment of the Japan Sea during the late Miocene is key to understand the evolution of the East Asian climate and ocean system [1]. In this study, we performed in situ chemical compositional analysis using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) on late Miocene marine sediments from the Japan Sea. By examining the sedimentary components and redox conditions of the depositional environment, we aimed to elucidate the palaeoceanographic changes in the Japan Sea during this period.
We focused on a sediment sample collected from International Ocean Discovery Program (IODP) Hole U1430B in the western Japan Sea, which was deposited approximately 11.5 Ma [2]. This interval contains distinct millimeter-scale dark and light layers that may reflect paleoceanographic variations on a 10-to 20-year timescale [2]. Because these samples are unconsolidated, appropriate preparation processes such as resin embedding and polishing are required before LA-ICP-MS analyses. After establishing suitable preparation methods, we performed LA-ICP-MS analyses on the dark–light layers to obtain distribution maps of major and trace elements, as well as quantitative determinations using matrix-matched standards.
In this presentation, we report on the LA-ICP-MS methods developed for unconsolidated marine sediments and provide preliminary interpretations of the paleoceanographic conditions of the late Miocene Japan Sea based on our analytical results.
[1] Tada (1994) Paleogeogr. Paleoclim. Paleoecol. 369, 1383–1387. [2] Kurokawa et al. (2019) Proc. Earth Planet. Sci. 6, 2.
We focused on a sediment sample collected from International Ocean Discovery Program (IODP) Hole U1430B in the western Japan Sea, which was deposited approximately 11.5 Ma [2]. This interval contains distinct millimeter-scale dark and light layers that may reflect paleoceanographic variations on a 10-to 20-year timescale [2]. Because these samples are unconsolidated, appropriate preparation processes such as resin embedding and polishing are required before LA-ICP-MS analyses. After establishing suitable preparation methods, we performed LA-ICP-MS analyses on the dark–light layers to obtain distribution maps of major and trace elements, as well as quantitative determinations using matrix-matched standards.
In this presentation, we report on the LA-ICP-MS methods developed for unconsolidated marine sediments and provide preliminary interpretations of the paleoceanographic conditions of the late Miocene Japan Sea based on our analytical results.
[1] Tada (1994) Paleogeogr. Paleoclim. Paleoecol. 369, 1383–1387. [2] Kurokawa et al. (2019) Proc. Earth Planet. Sci. 6, 2.