火星の熱帯から中緯度の雪と氷の蓄積,流れ,氷河化が火星に起きました
J W Head1, G Neukum, R Jaumann
1Department of Geological Sciences, Brown University, Providence, Rhode Island 02912, USA. james_head@brown.edu
Nature
|March 18, 2005
まとめ
最近のMars Expressの画像は,熱帯および中緯度の地域で氷に富んだ氷河堆積を明らかにし,地質学的に最近の気候変化を示しています. これらの発見は,将来の探査ミッションのためのアクセス可能な氷の貯蔵量を示唆しています.
科学分野:
- 惑星科学は惑星科学である.
- 氷河学 氷河学とは
- 火星地質学 火星地質学 火星地質学
背景:
- 火星のマッシフ基地の瓦の敷き布団は,複雑な地質学的特徴を示しています.
- 以前の研究では,火星の過去の氷河活動が示されましたが,最近の活動はあまり理解されていません.
研究 の 目的:
- 火星のHellasとOlympus Mons地域における地質学的に最近の氷河活動の証拠を調査する.
- 将来の探査のために,これらの埋蔵地内の氷の組成とアクセシビリティを評価する.
主な方法:
- マース・エクスプレス軌道探査機からの高解像度ステレオカメラ (HRSC) 画像の分析.
- 瓦の敷き布団,ロベットの特徴,ピッティングなどの地形学的特徴の解釈.
- ギリシャ東部の鉱床と,オリンポス・モンスの崖の底にある鉱床の比較.
主要な成果:
- 氷に富んだ粘着性の流れと昇華を示す多数の同心的な,ロバド,そしてピットした特徴の識別.
- オリンパス山の古い氷河の上に重ねた最近の氷に富んだ岩氷の発見.
- 軸傾斜が増加した期間に,低緯度の地域で氷河活動が繰り返されている証拠.
結論:
- 火星は,地質学的に最近,熱帯と中緯度の地域で繰り返される氷河活動を経験してきました.
- これらの堆積物には豊富な残留氷が含まれており,貴重な気候記録を提供しています.
- 特定された氷の豊富な埋蔵地は,将来のロボットと人間の探査のためのアクセス可能なターゲットです.
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