ウランシリーズは,エジプト南部のウチゲン炭酸とアケウリアン遺跡で年代付けされた
Science (New York, N.Y.)
|February 24, 1989
まとめ
エジプトで発見されたアケウリアン時代の遺物.
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
- 四次地質学 四次地質学
背景:
- アシュエル人遺物は,初期の人類の祖先と関連付けられた石器です.
- 南エジプトの非常に乾燥した環境は,古代の証拠の保存に課題を投げかけています.
- パレオバレーは,過去の人類の定住地のための潜在的な避難所を提供しています.
研究 の 目的:
- エジプト南部の古渓谷における初期の人類の居住を調査する.
- アケウリアの遺物埋蔵の時間的枠組みを確立する.
- アーティファクトの存在と古気候条件を相関させるため.
主な方法:
- ワディ・アリドとワディ・サフサフでのフィールド調査.
- オーチジェニック炭酸塩堆積物における人工物の識別.
- 25個の炭酸塩のサンプルをウランシリーズで年代測定した.
主要な成果:
- アチェウリア時代の遺物は,CaCO (((3)) -セメント付のアルービウムの中で in situ で発見されました.
- ウラン・シリーズ・デッティングにより,約45,141,212カロンの炭酸堆積が明らかになった.
- 古代バレーにおけるアチェウリア人の居住には,最低年齢が212kaと定められた.
結論:
- 炭酸塩の堆積が広範囲に広がっていることは,過去の湿気気候のエピソードを示唆しています.
- これらの湿気のある時期は,おそらくこの地域における人間の定住を容易にした.
- この発見は,エジプトのこの地域での初期の人間の存在のタイムラインを後退させる.
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