まとめ
放射性炭素年代測定により,カリフォルニア州サニーヴェールの現代人の骨格が明らかにされ,以前考えられていたよりも若いことが判明しました. この発見は,中期ホロセーン時代,つまり3500年から5000年前のことを示唆している.
科学分野:
- 古人類学は,古人類学である.
- ラジオメトリック・デッティング
- 考古学考古学とは
背景:
- カリフォルニア州サニーヴェールで,形態学的に現代的な人間の骨格が発見された.
- アスパルティック酸のラセミゼーションとウラン系同位体を用いた以前の年代測定は,相反する年代測定結果をもたらした.
研究 の 目的:
- カーボン14年代測定法を使用してサンニヴェール骨格の年齢を正確に決定するために.
- 人間の遺骸の以前の年齢推定における不一致を調和させるため.
主な方法:
- 複数の炭素14 (14C) 年代測定分析は,頭蓋骨後部の有機分子の上で行われました.
- 14Cの測定には,分解計数と直接計数の両方を使用した.
主要な成果:
- 4つの独立した14Cの決定が一貫して,骨格の中期ホロセンの年齢を示しました.
- 推定年齢の範囲は,現在より約3500〜5000年前の炭素14年です.
- この改訂された年代測定は,地質学,考古学,人類測定データと一致しています.
結論:
- カーボン14年代測定は,サニーヴェール骨格のより信頼できる年齢評価を提供します.
- 骨格は,以前の年代測定技術によって示唆されたよりもかなり若い.
- 発見は,埋葬のための中 Holocene 文脈をサポートします.
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