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火星上のチャズマ・ボレアルの建設
J W Holt1, K E Fishbaugh, S Byrne
1Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin, Austin 78758, Texas, USA. jack@ig.utexas.edu
Nature
|May 28, 2010
まとめ
火星の北極の層状積層は,主に侵食ではなく,不均等な氷の蓄積によって形成されました. このプロセスは,チャズマ・ボレアルを生み出し,火星の気候の歴史を形作りました.
科学分野:
- 惑星科学は惑星科学である.
- 地質学 地質学 地質学
- 気候科学 気候科学
背景:
- 火星の北極層層堆積 (NPLD) は,重要な水氷と気候記録を保持しています.
- NPLD内のチャズマ・ボレアルの形成は議論されており,その主要な仮説は侵食である.
研究 の 目的:
- チャズマ・ボレアールとNPLDの形成メカニズムを調査する.
- 火星の極地風景と古気候を形作る過程を理解する.
主な方法:
- 火星偵察軌道探査機からの新しいデータの分析.
- チャズマ・ボレアールと周辺のNPLDのストラティグラフィック分析.
主要な成果:
- チャズマ・ボレアルは主にNPLDの不均一な堆積から形成されたもので,侵食だけではありません.
- 以前から存在していた地形は,NPLDの堆積とそれに続く侵食パターンに影響を与えました.
- 証拠は,現在埋もれた第二の谷が存在していたことを示しており,複雑な堆積の歴史を示しています.
結論:
- 不均一な堆積過程と質量バランス,壊滅的な侵食ではなく,チャズマ・ボレアルの形をした.
- 以前から存在していた火星の地形は,極地層の堆積物形成に重要な役割を果たしました.
- NPLDの複雑な歴史は,火星の古気候と地質進化の洞察を明らかにしています.
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01:34Crossing Over
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The homologous pairs of sister chromosomes—one from the maternal and one from the paternal genome—then begin to align alongside each other lengthwise, matching corresponding DNA positions in a process called synapsis.
In order to...
02:50Spindle Assembly
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02:02Meiosis II
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The timing and cell division patterns of meiosis differ between males and females. In male meiosis, the centrosomes are part of the formation of the meiotic spindle. However, in oocytes, including that of humans, Drosophila,...
The timing and cell division patterns of meiosis differ between males and females. In male meiosis, the centrosomes are part of the formation of the meiotic spindle. However, in oocytes, including that of humans, Drosophila,...
01:30Crossing Over
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