ミランコビッチの仮説は,サンゴ礁と深海の沈殿物の正確な年代測定によって支持されています
まとめ
バーバドス・バーバドスとは
科学分野:
- 海洋地質学 海洋地質学
- 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
- サンゴ礁の研究研究
背景:
- バーバドスのサンゴ礁のテラスには,ユニークな地質学的な記録があります.
- 島の均一な上昇率は,海面の変化の研究を容易にする.
研究 の 目的:
- バーバドスの地質学的な特徴を用いて,プレイストセンの後半の海面の高さを再構築する.
- 海平面の変動と地球の気候と軌道周期を相関させるため.
主な方法:
- トリウム-230:ウラン-234 (Th(230:U(234) とプロタクトニウム-231:ウラン-235 (Pa(231):U(235) を用いた高精度の放射線年代測定法).
- 珊瑚礁と深海のコアの分析.
主要な成果:
- 約12万2千,10万3千,8万2千年前の3つの異なる海面の高さを特定しました.
- エリクソンのW-X気候現象を約12万6千年前と年代付けした.
- 地球の気候,海面の変化,そして過去15万年の夏の太陽照射サイクルを予測するとの相関を示した.
結論:
- バーバドスの上昇したサンゴ礁は,過去の海面を再構築するための信頼できるアーカイブを提供します.
- プレイストセンの後半の海平面の変動は,地球の軌道の変化と,その結果生じる気候変動と密接に関連しています.
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