主群のパラサイト母体におけるダイナモの証拠
John A Tarduno1, Rory D Cottrell, Francis Nimmo
1Department of Earth and Environmental Sciences, University of Rochester, Rochester, NY 14627, USA. john.tarduno@rochester.edu
まとめ
パラサイト隕石は,インパクター・コアが原惑星に液体金属を注入したときに形成された.
科学分野:
- 惑星科学は惑星科学である.
- 宇宙化学 (コスモケミストリー)
- 地質物理学 地質物理学とは地質物理学です.
背景:
- パラサイトは,オリビン結晶と鉄ニッケル金属で構成された石と鉄の隕石です.
- 隕石の形成の起源は,隕石の研究における長年の謎のままである.
研究 の 目的:
- パラサイト隕石の起源を調査する.
- 形成に伴う条件とプロセスを理解する.
主な方法:
- パラサイトオリビンの内部にある微小な磁気インクルージョンの分析.
- 磁場強度を測定するためのパレオ強度測定.
- 原惑星体の熱モデリング.
主要な成果:
- パラサイトオリビンは,優れた記録特性を持つ磁気含有物を含んでいます.
- 古磁気データは,ダイナモの作用を示す強力な磁場を明らかにしています.
- 形成モデルは,原惑星のマントルに液体金属の注入を示唆しています.
結論:
- パラサイトは,おそらく,原惑星の浅いマントルにインパクターの中心から液体鉄ニッケルを注入することによって形成された.
- 原惑星は衝突後何百万年もの間無傷のままであり,パラサイト形成を可能にしました.
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