Radiocarbon dating and wiggle matching of wooden poles forming circular structures in the 1st Millennium BC at the Mawaki archaeological site, central Japan

Wooden circular structures, presumed archaeologically as a structure related with ritual of ancient people in the Final Jomon period, are specific to archaeological sites excavated mainly in the coastal region around Noto peninsula, central Japan. So far, only few attempts have been made at chronological studies on these wooden structures. 14C dating has been attempted to wooden poles forming the structures, which had been excavated at the Mawaki archaeological site, Ishikawa prefecture, central Japan, to examine construction period of the structures. It was revealed that these structures were constructed in the Final Jomon period, most probably within 900–400 cal BC. In addition, we have tried wiggle matching of 14C ages for several annual rings separated from three and two poles that were constituting two circular structures, the oldest and the newest ones. 14C dates of annual rings measured with AMS were wiggle-matched to IntCal04 data sets by Bayesian statistics. The results indicated that the construction period of these wooden structures can be placed within ca. 820–680 cal BC, being narrowed by about 350 calendar years successfully.