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Zhoukoudian Homo erectusの年齢は, (26) Al/(10) Beの埋葬年代測定で決定されました
Guanjun Shen1, Xing Gao, Bin Gao
1College of Geographical Sciences, Nanjing Normal University, Nanjing, Jiangsu 210046, China. gjshen@njnu.edu.cn
Nature
|March 13, 2009
まとめ
新しい年代測定法により,チョウクーディアン・ホモ・エレクトス (Peking Man) が,これまで考えられていたよりも古くなっていることが明らかになった. この研究は,中国での初期のホミニン存在のより正確な年齢を提供し,約0.77百万年前の遺跡を年代付けします.
科学分野:
- 古人類学は,古人類学である.
- ジオクロノロジー (Geochronology) について
- 考古学考古学とは
背景:
- 昭和時代のホモ・エレクトス (北京人) の正確な年齢は,年代測定方法の限界のために決定することが困難でした.
- 以前のペキングマンの年齢の推定は問題があり,東アジアにおける初期のホミニン存在の明確な理解を妨げていた.
研究 の 目的:
- ゾウクーディアンホモ・エレクトス化石と関連する文化層のより正確な年齢を確立するために.
- 中国の初期のホミニン遺跡に新しい放射性同位体年代測定技術を適用する.
主な方法:
- コスモジェニック (26) アール/ 〇〇) は,場所1の地下層のクォーツ堆積物と人工物の埋葬年代付けである.
- スペレオテムカルシートのUシリーズ年代測定,古磁気層図,および堆積物学的データの統合.
主要な成果:
- ゾウクーディアンホモエレクタスの下層文化層7-10の加重平均年齢は0.77 ±0.08百万年である.
- これらの発見は,Uシリーズ年代測定の範囲を超えた中国のホミニン遺跡の最初の放射性同位体年代測定を表しています.
- 年代付けされた層は,中国のロース層学S6-S7または海洋同位体段階 (MIS) 17-19 (約0.68〜0.78百万年前) と相関しています.
結論:
- Zhoukoudian Homo erectusの年齢は,以前に推定されたよりもかなり古いです.
- これらの古い年代は,より穏やかな氷河期 (MIS 18) の中,中国北部の初期のホミニン占拠を示唆しています.
- この研究は,東アジアにおける初期のヒトの進化に関する重要な時間的枠組みを提供します.
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