石川県御絬塿遺踖から出土した縤文時代後・晩期土器の年代学的研究

摘要

石川県御経塚遺跡から出土した縄文時代後・晩期の土器付着物と漆の~(14)C年代，炭素・窒素安rn定同位体比，C/N比の測定を行い，土器で煮炊きされた内容物と各土器型式の年代学的位置づけrnについて検討した．その結果，後期の内面付着炭化物は，動物資源を煮炊きしたものが炭化してrn残ったものと考えられ，このうちのいくつかば海洋リザーバー効果の影響を受けている可能性をrn指摘した．晩期の土器付着物の~(14)C年代は，周辺地域の研究成果と対比しても整合的であった．そrnこで，晩期の土器付着物の~(14)C年代をIntCal04で較正し，晩期中葉の中屋式，晩期後葉の下野式rnおよび長竹式の較正年代を提示した．晩期最終末の長竹式の年代は，北陸地域における環状木柱rn列の形成時期とも関係することが明らかとなり，これは縄文時代から弥生時代への移行期の問題rnを検討する上で，きわめて重要な成果である．%In order to determine the absolute dates of the pottery types during the Late and Final Jomon periods in the area surrounding the Noto Peninsula, and to consider the origin of charred residues on the pottery, the authors examined ~(14)C dates, carbon and nitrogen stable isotopes and C/N ratios of the charred residues and lacquer-coats on potteries excavated at Okyozuka site, Ishikawa, Japan. Carbon and nitrogen stable isotope analysis and C/N ratios have revealed that all of the food residues collected from the inner surface of potsherds during the Late Jomon period seem to be derived from animal protein, and some of these food residues seem to be affected by marine reservoir effect. On the other hand, the Final Jomon potteries showed normal values of the isotope values and C/N ratios, and ~(14)C results were consistent with those of surrounding areas. These ~(14)C dates of Final Jomon potteries were calibrated using IntCa104 calibration curve. The results show consistent correlation between ~(14)C dates and pottery type sequences : Nakaya type is placed ca. 3,200-2,850 cal BP (1,250-900 cal BC), Shimono type is ca. 2,950-2,800 cal BP (1,000-850 cal BC), and Naga-take type is ca. 2,750-2,650 cal BP (800-700 cal BC).