深海の堆積物におけるエオリアン生物学的破片:赤道氷河期の乾燥度を示す可能性のある指標
Science (New York, N.Y.)
|August 23, 1974
まとめ
大西洋の堆積物の中のオパール植物や藻は,過去の海洋温度を示しています. 涼しい海は,より多くの微生物化石と相関しており,氷河期間のサハラ砂漠の乾燥状態を示唆しています.
科学分野:
- 古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは
- 海洋地質学 海洋地質学
- パレオエコロジー (古生態学)
背景:
- オパルの植物石や淡水藻類は,陸上の微生物化石である.
- これらの微生物化石は,大気中の塵を介して海洋環境に運ばれます.
- 堆積物記録は,過去の気候と環境条件についての洞察を提供します.
研究 の 目的:
- 大西洋の堆積物と過去の海洋温度におけるオパール植物石とダイアトムの豊富さの関係について調査する.
- サハラ以南の源地域における古気候条件を再構築する.
主な方法:
- 赤道大西洋の沈殿体内にあるオパール植物や淡水藻類の分析.
- 微生物化石の豊富さと,過去180万年の海洋温度のプロキシとの相関.
- マイクロ化石の集合に基づいた古気候条件の推論.
主要な成果:
- オパルの植物石とダイアトムは,より冷たい海洋時代の堆積物には豊富に存在し,より暖かい時期の堆積物には稀に存在します.
- このパターンは,過去180万年間も続いている.
- サハラ以南の源地の気候は,氷河期にはおそらくより乾燥し,氷河間期にはより湿ったものであった.
結論:
- 大西洋の堆積物における地上の微生物化石の豊富さは,過去の海洋温度の代理として機能します.
- サハラの気候の変化 (乾燥度/湿度) は,氷河期と氷河期間のサイクルに関連しており,大西洋への塵の輸送に影響を与えています.
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