河川ネットワークの破壊の結果,地上の低地形の景観の形成です
Rong Yang1, Sean D Willett1, Liran Goren2
1Geological Institute, Swiss Federal Institute of Technology, 8092 Zurich, Switzerland.
Nature
|April 24, 2015
まとめ
高度,低地形の景観は,古代の表面ではないかもしれません. 構造的変形は河川ネットワークを隔離し,低地形がin situで発達し,伝統的な景観の進化モデルに挑戦します.
科学分野:
- ジオモルフォロジー ジオモルフォロジー
- テクトニクス (地質学) とは
- 景観の進化 景観の進化
背景:
- ランドスケープは,地形構造と気候の歴史を記録しています.
- 均衡の地形は,通常,海平面に等級した,低地上の低浮き面を特徴とする.
- 高度,低地形の表面は,しばしば高揚した古代の風景として解釈されます.
研究 の 目的:
- ランドスケープの進化モデルを,リリクトランドスケープの進化モデルをテストする.
- チベット高原の東南部の高地,低地形の表面のデジタル地形を分析するために.
- 高い半平原の形成メカニズムを調査する.
主な方法:
- リリクトの景観のデジタル地形分析.
- 観測された地形データに対して,風景の進化の確立されたモデルをテストする.
- 代替的な景観の進化モデルを探求するための数学的実験.
主要な成果:
- 研究された表面は,新しい,より急な川の階層の漸進的な確立と矛盾しています.
- 表面は必ずしも古い低浮き景観の残骸を表しているわけではない.
- 構造的変形は,地域的な河川ネットワークを混乱させ,いくつかの地域を隔離したようです.
結論:
- 高い低地形表面は,過去の低地形状態の残骸ではないかもしれません.
- 代替モデルでは,構造的破壊が河川のネットワークを隔離し,低地形の開発を現場で行うことを示唆している.
- 低レリーフと低侵食率は,過去の侵食状態を保存するのではなく,特定の構造的条件下で in situ で発生することができます.
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