水星の地殻の進化:MESSENGERからのグローバルな視点

Brett W Denevi¹, Mark S Robinson, Sean C Solomon

¹School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85251, USA. bdenevi@ser.asu.edu

Science (New York, N.Y.)

|May 2, 2009

まとめ

水星の地殻は,火山の平原が表面の40%を占める多様な地形を示しています. 衝撃噴出物には,おそらくより深い層からの青い,低反射性の物質が発見され,地殻とマントルの組成を明らかにしています.

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
リモートセンシング (リモートセンサー)

背景:

惑星の地殻の組成と進化を理解することは,惑星の形成と歴史を制限するために不可欠です.
以前の水星の観測は限られた範囲で実施され,その表面の特徴の包括的な分析を妨げていた.

研究の目的:

水星の表面上の主要な地形タイプの分布と範囲をマッピングする.
水星の地殻の組成の横と垂直の異質性を,色違いを用いて明らかにする.

主な方法:

MESSENGERとMariner 10のミッションから得られたデータを分析した.
組成を推論するために,表面反射率のスペクトル解析.

主要な成果:

火山活動を示す滑らかな平原は,水星の表面の約40%をカバーしています.
衝撃エジェクタに濃縮された独特の低反射度,青い色彩の材料は,表面の少なくとも15%をカバーします.
スペクトルの特徴は,この青い物質は,より深い地殻または上層マントルの層から,鉄とチタンの酸化物で富んでいることを示唆しています.

結論:

水星の地殻の大部分は,火山の過程で発生したと考えられます.
青い物質の存在と分布は,水星の内部構造と組成についての洞察を提供し,深部から発掘することを示唆しています.

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