Irの異常から生じたネオプロテロゾイク期の雪球氷河の期間と強度を推定する
Bernd Bodiselitsch1, Christian Koeberl, Sharad Master
1Department of Geological Sciences, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria.
まとめ
地外物質,特にイリジウム異常の証拠は,キャップ炭酸塩の底部で発見され,グローバルネオプロテロゾイク氷河とその急速な融解の理論を支持しています. これは,マリノの氷河期が長く続いたことを示している.
科学分野:
- 地質学 地質学 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
- アストロジオロジー アストロジオロジー
背景:
- ネオプロテロゾーイク時代は,超温室環境で終わり,急速な氷の融解とキャップ炭酸塩の形成を引き起こしました.
- グローバルな氷河化により,地球外物質が氷に集積し,融解の過程で氷が沈み落ちる.
研究 の 目的:
- ネオプロテロゾイク氷河とキャップ炭酸塩の境界で地外物質の存在を調査する.
- 世界的なネオプロテロゾイク氷河の範囲を確認し,マリノの氷河期間の期間を精査する.
主な方法:
- 東コンゴクレートンから採取した3つのドリルコアの分析.
- カップ炭酸層内のイリジウム (Ir) の異常を特定する.
主要な成果:
- すべての分析されたドリル・コアにおけるキャップ・カーボネートの底部で,有意なイリジウム異常が検出されました.
- これらの発見は,広範囲にわたる地球規模のネオプロテロゾイク氷河の発生を裏付けている.
- データは,マリノの氷河期が少なくとも300万年,そして潜在的に1200万年まで続いたことを示唆しています.
結論:
- イリジウム異常の存在は,ネオプロテロゾーイク氷河期における地球外物質の堆積の強力な証拠を提供します.
- この研究は,ネオプロテロゾーイク期の氷層,特にマリノアの氷河期が,地球規模で存在し,その期間が長かったことを確認しています.
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