Fine Structure and Reproducibility of Radiocarbon Ages of Middle to Early Modern Japanese Tree Rings

This study carried out accelerator mass spectrometry radiocarbon (AMS 14C) measurement of Japanese tree rings dating from the middle to early modern eras to investigate calibration curve fine structure. Tree-ring ages were determined by dendrochronology or δ18O chronology for Japanese trees. 14C ages from the 15th century to the middle of the 17th century followed the IntCal13 calibration curve within measurement error. Different patterns of fluctuations during the latter half of the 17th century to the early the 18th century were observed in different tree samples. In the 19th century, patterns of 14C ages of different samples appeared similar but did not exactly match each other.