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Updated: Jul 12, 2026

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Atom Probe Tomography Analysis of Exsolved Mineral Phases
Published on: October 25, 2019
まとめ
南極の地殻下部の粒子を調査すると,重要な構成と年齢の不連続性が明らかになる. ストロンチウムと酸素のイソトープによって特定されたこの地質学的境界線は,南極横断の山脈の下にある古代の縫合物を示す可能性があります.
科学分野:
- 地質化学 地質化学
- ペトロロジー・ペトロロジーとは
- テクトニクス (地質学) とは
背景:
- 下層の大陸地殻の構成と進化は,未だに十分に理解されていない.
- 地殻の異質性を理解することは,地球の地殻-マントルのダイナミクスを解読する鍵です.
研究 の 目的:
- 南極大陸のマクマードー・サウンド地域における下層大陸地殻の性質と構成の異質性を調査する.
- ストロンチウムと酸素のイソトープ,主要元素および下層地殻の粒状インクルージョンの微量元素を分析するために.
主な方法:
- 南極の火山岩からの20以上の粒状岩の含有物の分析.
- ストロンチウムと酸素同位体の地化学.
- メジャーと微量元素の分析.
主要な成果:
- 下層地殻の組成と年齢の明確な不連続性が確認されました.
- この不連続性は,南極横断山脈とロス湾の境界線と一致しています.
- 同位体差異により,この境界線は古代の地殻の縫い目を表している可能性があることが示唆されています.
結論:
- マクマルドー・サウンド地域の地殻の下部は,著しい異質性を示しています.
- 観測された境界線は,長生きした地形構造の特徴,おそらく古代の縫合地帯を意味する可能性があります.
- 現在のケノゾイク期の裂け目が,この古い地殻の境界を活性化しているのかもしれない.
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