TY - JOUR
T1 - Integrated tephrostratigraphy and stable isotope stratigraphy in the Japan Sea and East China Sea using IODP Sites U1426, U1427, and U1429, Expedition 346 Asian Monsoon
AU - Sagawa, Takuya
AU - Nagahashi, Yoshitaka
AU - Satoguchi, Yasufumi
AU - Holbourn, Ann
AU - Itaki, Takuya
AU - Gallagher, Stephen J.
AU - Saavedra-Pellitero, Mariem
AU - Ikehara, Ken
AU - Irino, Tomohisa
AU - Tada, Ryuji
N1 - Funding Information:
This work was partly supported by the IODP Exp. 346 After Cruise Research Program, JAMSTEC and by “Collaborative Study of Long-term Changes in the Asian Monsoon” of Program for Advancing Strategic International Networks to Accelerate the Circulation of Talented Researchers, Japan Society for the Promotion of Science. AH gratefully acknowledges institutional funding from Christian-Albrechts-University.
Publisher Copyright:
© 2018, The Author(s).
PY - 2018/3/22
Y1 - 2018/3/22
N2 - Integrated Ocean Drilling Program Expedition 346 “Asian Monsoon” obtained sediment successions at seven sites in the Japan Sea (Sites U1422–U1427 and U1430) and at two closely located sites in the northern East China Sea (Sites U1428 and U1429). The Quaternary sediments of the Japan Sea are characterized by centimeter- to decimeter-scale dark–light alternations at all sites deeper than 500 m water depth. The sedimentary records from these sites allow an investigation of the regional environmental response to global climate change, including changes in the Asian Monsoon and eustatic sea level. However, the discontinuous occurrence of calcareous microfossils in the deep-sea sediments and their distinct isotope signature that deviates from standard marine δ18O records do not permit the development of a detailed stable isotope stratigraphy for Japan Sea sediments. Here, we present the tephrostratigraphy for the two southernmost sites drilled in the Japan Sea (Sites U1426 and U1427) and for one site drilled in the East China Sea (Site U1429) along with the benthic δ18O isotope stratigraphy for the shallower Site U1427 and the East China Sea Site U1429. Eighteen tephra layers can be correlated between sites using the major-element composition and morphology of volcanic glass shards, and the compositions of grains and heavy minerals. Tephra correlations show that negative δ18O peaks in the Japan Sea correspond to positive glacial maxima peaks in the East China Sea. Using this integrated stratigraphic approach, we establish an orbital-scale age model at Site U1427 for the past 1.1 Myr. The correlation of tephra layers between the shallower Site U1427 (330 m below sea level: mbsl) and the deeper Site U1426 (903 mbsl) in the southern Japan Sea provides the opportunity for further age constraints. Our results show that alternations in sediment color at Sites U1426 and U1427 can be correlated for the past 1.1 Myr with minor exceptions. Thus, the stable isotope stratigraphy established at the shallower Site U1427 can be correlated to Site U1426, and in turn to all sites drilled during Expedition 346, based on correlations of dark–light layering.
AB - Integrated Ocean Drilling Program Expedition 346 “Asian Monsoon” obtained sediment successions at seven sites in the Japan Sea (Sites U1422–U1427 and U1430) and at two closely located sites in the northern East China Sea (Sites U1428 and U1429). The Quaternary sediments of the Japan Sea are characterized by centimeter- to decimeter-scale dark–light alternations at all sites deeper than 500 m water depth. The sedimentary records from these sites allow an investigation of the regional environmental response to global climate change, including changes in the Asian Monsoon and eustatic sea level. However, the discontinuous occurrence of calcareous microfossils in the deep-sea sediments and their distinct isotope signature that deviates from standard marine δ18O records do not permit the development of a detailed stable isotope stratigraphy for Japan Sea sediments. Here, we present the tephrostratigraphy for the two southernmost sites drilled in the Japan Sea (Sites U1426 and U1427) and for one site drilled in the East China Sea (Site U1429) along with the benthic δ18O isotope stratigraphy for the shallower Site U1427 and the East China Sea Site U1429. Eighteen tephra layers can be correlated between sites using the major-element composition and morphology of volcanic glass shards, and the compositions of grains and heavy minerals. Tephra correlations show that negative δ18O peaks in the Japan Sea correspond to positive glacial maxima peaks in the East China Sea. Using this integrated stratigraphic approach, we establish an orbital-scale age model at Site U1427 for the past 1.1 Myr. The correlation of tephra layers between the shallower Site U1427 (330 m below sea level: mbsl) and the deeper Site U1426 (903 mbsl) in the southern Japan Sea provides the opportunity for further age constraints. Our results show that alternations in sediment color at Sites U1426 and U1427 can be correlated for the past 1.1 Myr with minor exceptions. Thus, the stable isotope stratigraphy established at the shallower Site U1427 can be correlated to Site U1426, and in turn to all sites drilled during Expedition 346, based on correlations of dark–light layering.
KW - East China Sea
KW - Expedition 346
KW - Integrated Ocean Drilling Program
KW - Inter-site correlation
KW - Japan Sea
KW - Stable isotope stratigraphy
KW - Tephrostratigraphy
UR - http://www.scopus.com/inward/record.url?scp=85044385462&partnerID=8YFLogxK
U2 - 10.1186/s40645-018-0168-7
DO - 10.1186/s40645-018-0168-7
M3 - Article
AN - SCOPUS:85044385462
SN - 2197-4284
VL - 5
JO - Progress in Earth and Planetary Science
JF - Progress in Earth and Planetary Science
IS - 1
M1 - 18
ER -