氷で覆われたフィヨルドの景観によって示唆されるダイナミックな初期の東南極氷床
Duncan A Young1, Andrew P Wright, Jason L Roberts
1Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin, Austin, Texas 78758, USA. duncan@utig.ig.utexas.edu
Nature
|June 4, 2011
まとめ
南極大陸は南極で
科学分野:
- 地質学 地質学 地質学
- 氷河学 氷河学とは
- 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,古代気候学 (paleoclimatology) とは
背景:
- 南極大陸では地球温暖化によってケノゾイク期の氷床が形成された.
- 周期的な氷床の膨張と後退は,海平面に影響を及ぼし,30回まで発生しました.
- 氷床の振動は,南極の地形的な低地に依存しています.
研究 の 目的:
- 東南極のオーロラ亜氷河盆地の基礎地形を調査するために.
- 過去の氷床の構成にトポグラフィの影響を理解する.
- 氷の流れによって形成された風景の歴史を明らかにするために.
主な方法:
- 新しい氷を貫通するレーダーデータの分析.
- 堆積物の配列の解釈. 堆積物の配列の解釈.
- 数値的な氷床モデリング.
主要な成果:
- オーロラ亜氷河盆地における地形学的な運河を備えたフィヨルドの景色を特定した.
- 過去の氷床の構成によって彫刻された複雑な表面を明らかにした.
- 氷床の縁が波動の間,盆地縁に沿って固定されていることを示した.
結論:
- オーロラ亜氷河盆地の地形は,過去の氷の流れによって彫られた運河によって特徴付けられています.
- 過去の氷床の構成は,現在のものとは大きく異なっていた.
- フィヨルドの風景は,深い低谷の上に複数の氷の流れによって形成されました.
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