下層マントルのフェロペリカラーゼの安定性
Dubrovinsky1, Dubrovinskaia, Saxena
1Institute of Earth Sciences, Uppsala University, S-752 36 Uppsala, Sweden. European Synchrotron Radiation Facility (ESRF), BP 220, F-38043 Grenoble Cedex, France.
Science (New York, N.Y.)
|July 21, 2000
まとめ
下層マントルの重要な鉱物であるフェロペリカラーゼは,極端な圧力と温度下では,マグネシウムに富むと鉄に富むと異なる相に分解することがあります. この解離は,ダイナミックな効果を誘導し,マントルの異質性に寄与する可能性があります.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- ミネラル物理学 ミネラル物理学
- 地球科学 地球科学 地球科学
背景:
- フェロペリクラゼは,地球の下層マントルの主要な成分です.
- マントル条件下でのその安定性と行動を理解することは,地震データを解釈し,マントルダイナミクスをモデル化するために重要です.
研究 の 目的:
- フェロペリクラゼ固体溶液の安定性と潜在的な解離を,高圧と高温で調査する.
- 地球の下層マントルに関連する条件をシミュレートするために.
主な方法:
- フェロペリクラゼのサンプル ((Mg(0.60) Fe(0.40)) Oと (Mg(0.50) Fe(0.50)) Oを86ギガパスカルの温度で1000ケルビンまで加熱する.
- マオ・ベル型のダイヤモンド・アンビル・セルでX線 difraktion を利用する.
主要な成果:
- フェロペリカラーゼのサンプルでは,マグネシウムに富んだ酸化物と鉄に富んだ酸化物に分解する可能性があることが示された.
- 観測された分解は,下層マントルの条件下で鉱物の振る舞いを洞察する.
結論:
- フェロペリクラゼの分解は,異なる相に分解され,密度の変化につながる可能性があります.
- これらの密度差は,地球マントルの化学的および物理的な異質性に寄与する,ダイナミックなプロセスを駆動する可能性があります.
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