High-resolution and high-precision correlation of dark and light layers in the Quaternary hemipelagic sediments of the Japan Sea recovered during IODP Expedition 346

• Main Authors: Ryuji Tada, Tomohisa Irino, Ken Ikehara, Akinori Karasuda, Saiko Sugisaki, Chuang Xuan, Takuya Sagawa, Takuya Itaki, Yoshimi Kubota, Song Lu, Arisa Seki, Richard W. Murray, Carlos Alvarez-Zarikian, William T. Anderson, Maria-Angela Bassetti, Bobbi J. Brace, Steven C. Clemens, Marcio H. da Costa Gurgel, Gerald R. Dickens, Ann G. Dunlea, Stephen J. Gallagher, Liviu Giosan, Andrew C. G. Henderson, Ann E. Holbourn, Christopher W. Kinsley, Gwang Soo Lee, Kyung Eun Lee, Johanna Lofi, Christina I. C. D. Lopes, Mariem Saavedra-Pellitero, Larry C. Peterson, Raj K. Singh, Samuel Toucanne, Shiming Wan, Hongbo Zheng, Martin Ziegler
• Format: Article
• Language: English
• Published: SpringerOpen 2018-03-01
• Series: Progress in Earth and Planetary Science
• Subjects: Quaternary sediments; Japan Sea; Inter-site correlation; High-resolution age model; IODP; Expedition 346
• Online Access: http://link.springer.com/article/10.1186/s40645-018-0167-8

Abstract The Quaternary hemipelagic sediments of the Japan Sea are characterized by centimeter- to decimeter-scale alternation of dark and light clay to silty clay, which are bio-siliceous and/or bio-calcareous to a various degree. Each of the dark and light layers are considered as deposited synchronously throughout the deeper (> 500 m) part of the sea. However, attempts for correlation and age estimation of individual layers are limited to the upper few tens of meters. In addition, the exact timing of the depositional onset of these dark and light layers and its synchronicity throughout the deeper part of the sea have not been explored previously, although the onset timing was roughly estimated as ~ 1.5 Ma based on the result of Ocean Drilling Program legs 127/128. Consequently, it is not certain exactly when their deposition started, whether deposition of dark and light layers was synchronous and whether they are correlatable also in the earlier part of their depositional history. The Quaternary hemipelagic sediments of the Japan Sea were drilled at seven sites during Integrated Ocean Drilling Program Expedition 346 in 2013. Alternation of dark and light layers was recovered at six sites whose water depths are > ~ 900 m, and continuous composite columns were constructed at each site. Here, we report our effort to correlate individual dark layers and estimate their ages based on a newly constructed age model at Site U1424 using the best available paleomagnetic datum and marker tephras. The age model is further tuned to LR04 δ18O curve using gamma ray attenuation density (GRA) since it reflects diatom contents that are higher during interglacial high-stands. The constructed age model for Site U1424 is projected to other sites using correlation of dark layers to form a high-resolution and high-precision paleo-observatory network that allows to reconstruct changes in material fluxes with high spatio-temporal resolutions.