氷河の影響により,山の高さが制限されています
D L Egholm1, S B Nielsen, V K Pedersen
1Department of Earth Sciences, Aarhus University, DK-8000 Aarhus, Denmark. david@geo.au.dk
Nature
|August 14, 2009
まとめ
山脈の高さは主に地質学的な力ではなく,気候によって制御されます. 気候の影響による雪面による氷河の侵食と静止上昇が,山の最大高度を決定する.
科学分野:
- 地球科学 地球科学 地球科学
- 地質学 地質学 地質学
- 気候学 気候学
背景:
- 山脈の高さは,構造的上昇,地殻の強度,表面の剥離のバランスによるものです.
- 構造的変形,荒廃,気候の相互作用は,科学的な議論の重要な分野である.
- 気候,特に降水と氷河は,露出率と山岳地形に影響を与えます.
研究 の 目的:
- 気候,特にスノーラインの高さ,および全世界の山脈の最大高度との関係を調査する.
- 氷河侵食が"氷河バズソー"メカニズムを通じて山の高さに影響するという仮説を検証する.
- 気候や地質学力が山脈の高さを支配する支配的要因であるかどうかを判断する.
主な方法:
- トポグラフィックデータのグローバル分析.
- 最大山の高さと気候制御されたスノーラインの高さグラデーションの相関分析.
- 侵食および静態化のプロセスをシミュレートするための数値モデリング.
主要な成果:
- 最大山の高さと,様々な山脈の気候制御されたスノーラインの高さグラデーションの間に強い相関が見られた.
- 数値モデルにより,氷河の侵食が雪線上にあることと,その後の同静的上昇が,雪線下にある窓に向かって山の高さを押し上げることが示されました.
- このモデルは,氷河のバズソウメカニズムに関連したヒプソメトリックシグネチャを成功裏に再現しました.
結論:
- 気候は,氷河期およびその脱毛と安定性への影響を通じて,最大山脈の高さの主要な要因です.
- 地質学的な力は,気候と比較して,山脈の最終的な高さを決定する上で,より小さな役割を果たします.
- "氷河バズソー"は,山の地形を形作る,最大標高を制限する効果的なメカニズムです.
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