Institute for Space-Earth Environmental Research, Nagoya University
Atmosphere and Ocean Research Institute, The University of Tokyo
抄録
Oxygen isotopes of biogenic calcium carbonate can be used to reconstruct salinity if the oxygen isotope–salinity (δ18O–S) relationship for the region of interest is known. In Otsuchi Bay, located on the northeast coast of Japan, δ18O–S relationship has been reported; however, the data were only collected from the mouth of the bay and covered a limited salinity range, which restricts the applicability of the relationship in reconstructions of salinity. This study is the first to establish a δ18O–S relationship for Otsuchi Bay that can be applied to a wide range of salinities, from zero (fresh water) to 34 (open ocean water), using water samples collected from September 2014 to September 2015 from the middle of the bay (Hourai-jima): The obtained relationship was δ18O=(0.28±0.01) S−(9.31±0.41), and the slope was shallower than that of the previous study. We also sampled waters in the lower reaches of the three main rivers that flow into Otsuchi Bay: the Otsuchi, Kozuchi and Unosumai rivers, and determined their oxygen and hydrogen isotope compositions. No statistically significant differences were detected between the rivers, and no distinct seasonality was observed. Calculated d-excess values of these newly obtained data are consistent with previously reported values of stream water collected in the region.
雑誌名
Coastal Marine Science
巻
41
号
1
ページ
1 - 6
発行年
2018
ISSN
13493000
書誌レコードID
AA11957899
著者版フラグ
publisher
出版者
International Coastal Research Center, Atmosphere and Ocean Research Institute, the University of Tokyo
Oxygen and hydrogen isotope characteristics of seawater in Otsuchi Bay and meteoric water of inflowing rivers
CMS410101.pdf
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