火星の堆積岩の記録における準周期的布団
Kevin W Lewis1, Oded Aharonson, John P Grotzinger
1Divison of Geological and Planetary Sciences, California Institute of Technology, 150-21, Pasadena, CA 91125, USA. klewis@gps.caltech.edu
まとめ
火星のリズミカル・ベッディング
科学分野:
- 惑星科学 惑星科学
- 地質学 地質学 地質学
- アストロジオロジー アストロジオロジー
背景:
- 火星の堆積岩は,今日の冷たく乾燥した環境とは異なる過去の環境を示しています.
- これらの潜在的に居住可能な条件の持続期間は,依然として不確実です.
研究 の 目的:
- 火星上の堆積に有利な過去の地表条件の持続時間を調査する.
- 火星の堆積岩のリズムを分析し,堆積の歴史を推測する.
主な方法:
- 1メートルのステレオトポグラフィックマップを使用して,堆積物の露出を特定し,分析しました.
- アラベア・テラ地域における複数の場所でのリズム的な床のパターンと厚さの比率を調査した.
主要な成果:
- いくつかの火星の露出地での堆積岩のリズム的な床の存在を証明した.
- 約10メートルの厚さの重複ベッドが特定され,より大きなユニットは10: 1の厚さ比を示しています.
- 何百メートルもの層が1つの場所でより大きな単位に束ねられていることを観察しました.
結論:
- 観測されたリズム的な布団は,火星の環境条件の周期性を示唆しています.
- この周期性は,軌道変動などの天文学的強制力に関連している可能性があります.
- これらの岩層の堆積は,何百万年にも及ぶ可能性があり,長期にわたる潜在的に居住可能な表面状態を示しています.
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