惑星科学:低速衝突で形成された隕石クレーター
1Lunar and Planetary Laboratory, University of Arizona, Tucson, Arizona 85721, USA. jmelosh@lpl.arizona.edu
Nature
|March 11, 2005
まとめ
隕石クレーターの形成には,鉄の隕石が地球に衝突し,約12km/sの速度で地球に衝突した. この予想より低い衝突速度は,クレーターに重要な衝突溶融岩が存在しないことを説明します.
科学分野:
- 地質学 地質学 地質学
- 惑星科学は惑星科学である.
- インパクトクラテリング (インパクトクラテリング)
背景:
- アリゾナ州にある隕石クレーターは,地上の隕石の衝突構造が最初に認められたものです.
- 広く研究されているが,その形成メカニズムは部分的に解明されていない.
研究 の 目的:
- 隕石クレーターの形成に起因した隕石の衝突速度を調査する.
- 衝突による溶融岩の欠如に関する不一致を解決するために.
主な方法:
- 隕石クレーターからの地質学的データの分析.
- 衝撃のダイナミクスのモデリング.
主要な成果:
- 鉄隕石の表面衝突速度は,約12 km/sと決定されました.
- この速度は,以前に想定された値 (15-20 km/s) よりも著しく低い.
結論:
- 衝突速度の低さは,隕石クレーターで観測された衝突溶融岩の限られた量を説明する.
- この発見は,クレーターの形成と関連する衝撃プロセスに関する私たちの理解を修正します.
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