Tree ring oxygen isotope dating of wood recovered from a canal in the ancient capital of Japan

Two New Millennium-Long Tree-Ring Oxygen Isotope Chronologies (2349–1009 Bce and 1412–466 Bce) From Japan

“…Because of the limited sample size, which is not sufficient for developing a tree-ring chronology, we also collected samples of Zelkova serrata and Quercus sp. Although tree-ring width patterns of these samples cannot be matched with those of the cedar samples, tree-ring δ 18 O values can be matched between conifer and broad-leaf trees (Sano et al 2022). A total of 34 samples, consisting of 28, 5, and 1 samples of Cryptomeria , Zelkova , and Quercus, respectively, were obtained from a lumber dealer and local authority.…”

“…Due to its strong climatic sensitivity, annual variations in tree-ring δ 18 O values are well correlated in samples from the same and different species. In addition, tree-ring δ 18 O time-series are also significantly correlated between samples that are spatially distant from each other (Seo et al 2019; Sano et al 2022). Recently a 2600-yr-long tree-ring record was developed for Japan using both oxygen and hydrogen isotopes, in order to reconstruct decadal–centennial hydroclimatic variability (Nakatsuka et al 2020).…”

“…Recently a 2600-yr-long tree-ring record was developed for Japan using both oxygen and hydrogen isotopes, in order to reconstruct decadal–centennial hydroclimatic variability (Nakatsuka et al 2020). The original δ 18 O time-series was then modified by extracting high-frequency components to produce a master chronology that is suitable for tree-ring dating (Sano et al 2022). While the updated δ 18 O chronology works well for dating archaeological samples with short tree-ring sequences (30–60 rings), the tree-ring δ 18 O chronology needs to be extended both spatially and temporally in Japan.…”

“…Dendrochronologically dated samples for the period 667–660 BCE were further used for radiocarbon measurements at sub-annual resolution, to verify our dates by identifying a rapid 14 C spike observed in Germany (Park et al 2017) and Japan (Sakurai et al 2020). In combination with a published tree-ring δ 18 O time-series from central Japan (Nakatsuka et al 2020; Sano et al 2022), our tree-ring δ 18 O dataset currently available for Japan covers the past 4354 yr (2349 BCE to 2005 CE), which represents the longest annually resolved tree-ring δ 18 O record for Asia. Tree-ring data for the master chronologies are archived as Supplementary Material to this article.…”

A WIGGLE-MATCHED 297-YR TREE-RING OXYGEN ISOTOPE RECORD FROM THAILAND: INVESTIGATING THE 14C OFFSET INDUCED BY AIR MASS TRANSPORT FROM THE INDIAN OCEAN

“…Compared with conventional dendrochronology based on ring widths, oxygen isotope ratios in tree rings are well correlated between different trees (e.g., Sano et al 2012aSano et al , 2012b. Therefore, tree-ring δ 18 O data can be used to robustly date a dataset with a limited number of tree-ring samples even if the ring width series cannot be cross-dated by conventional dendrochronological analysis (Loader et al 2019;Sano et al 2022). In addition, being controlled simply by two climatic parameters (i.e., the δ 18 O of precipitation and relative humidity), tree-ring δ 18 O can be used to precisely reconstruct past hydroclimatic variations, such as during the summer monsoon season in Southeast Asia (Sano et al 2012b;Xu et al 2013;Pumijumnong et al 2020).…”