まとめ
高圧実験では,オリヴィンとスピネル鉱物は,極端な条件下で不均衡に酸化マグネシウムと鉄の酸化物とステショビット (高圧形式のシリカ) に変化することを示しています. これは,地球深層の圧力下での新しい鉱物相変換を明らかにします.
科学分野:
- 地質化学 地質化学
- ミネラル物理学 ミネラル物理学
- 高圧科学 高圧科学とは
背景:
- オリバインとスピネルは,地球のマントルの主要な岩石形成鉱物です.
- 極端な圧力や温度下での彼らの行動を理解することは,地球深層の地力学にとって極めて重要です.
研究 の 目的:
- オリヴィンとスピネルの相変換を,高圧と高温で研究する.
- これらの鉱物における不均衡反応の産物を決定する.
主な方法:
- オリヴィンとスピネルの試料は,異なる組成で,ダイヤモンドのアンビルセルを使用して,最大250キロバーの圧力をかけました.
- 連続波のYAGレーザーを用いて~1700°Cまでのインシトゥー加熱を達成しました.
- 温度測定は,光学ピロメトリーを用いて行われました.
- 試料の組成を冷却と卸し後に分析するために,X線 difrraction が使用されました.
主要な成果:
- X線 difraktion パターンは,オリヴィンとスピネルが適用された条件下では不釣り合いであることを確認しました.
- 観察された製品は (Mg, Fe) Oとstishovite (SiO(s)) と特定されました.
結論:
- オリビンとスピネルは,250キロバーを超える圧力と約1700°Cの温度で (Mg, Fe) Oとスティショビットに不釣り合いを経験します.
- これらの発見は,鉱物の安定性と地球の深い内部の変容についての洞察を提供します.
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