地質学的環境と,南アフリカで発見されたAustralopithecus sedibaの年齢
Paul H G M Dirks1, Job M Kibii, Brian F Kuhn
1School of Earth and Environmental Sciences, James Cook University, Townsville, QLD 4811, Australia. paul.dirks@jcu.edu.au
Science (New York, N.Y.)
|April 10, 2010
まとめ
南アフリカで発見されたAustralopithecus sedibaの化石は,約1億9500万年前から178万年前まで遡ります. これらの初期の人類の祖先は,洞窟の堆積物の中で発見され,古代アフリカの古老環境についての洞察を提供しました.
科学分野:
- 古人類学は,古人類学である.
- 地質学 地質学 地質学
- クロノロジック・クロノロジック
背景:
- 南アフリカのマラパ遺跡には,Australopithecus sediba.の化石が含まれています.
- これらの化石は,2,36~150万年前のマクロファウナ集団と関連しています.
研究 の 目的:
- マラパ遺跡の地質学,地質年代学,地形学,動物学的な文脈を詳細に説明する.
- アウストラロピテクス・セディバの化石の正確な年代と堆積環境を確立するために.
主な方法:
- マラパ遺跡の地質学的および地形学的分析.
- フローストーン層の放射線年代測定法 (U-Pb)
- 堆積物の古磁気分析. 堆積物の古磁気分析. 堆積物の古磁気分析. 堆積物の古磁気分析.
- 動物の集合分析. 動物の集合分析.
主要な成果:
- ホミニンの化石は,流石の上の水に敷かれたクラスティック堆積物の中にあり,その年代は2.026 +/- 0.021万年前とされています.
- 古磁気データは,オルドゥヴァイ亜クロン (1.951.78 Ma) の間の堆積を示しています.
- 2匹のオストラロピテクス・セディバの標本が1つの瓦の流れで一緒に埋葬された.
結論:
- マラパ族のヒト族は,約1億9500万年前から178万年前まで生きた.
- 化石の堆積は洞窟系で発生し,沈殿物はフレーティックな環境で急速にリチ化する.
- この遺跡は,アフリカにおける初期のヒト類の進化と古生態学を理解するための重要な文脈を提供します.
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