鉄に富んだポストペロブスキートと超低速圏の起源
Wendy L Mao1, Ho-Kwang Mao, Wolfgang Sturhahn
1Lujan Neutron Scattering Center, Los Alamos National Laboratory, Los Alamos, NM 87545, USA. wmao@lanl.gov
Science (New York, N.Y.)
|April 29, 2006
まとめ
核-マントル境界の超低地震速度の地域は,鉄に富んだペロフスキート後のシリケートによって引き起こされる可能性があります. これらのシリケートは安定しており,コア-マントル反応によって形成され,観測可能な地震パッチに蓄積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
- 地震学 地震学とは
背景:
- 地球のコア-マントル境界 (CMB) は,超低地震速度の地域を示しています.
- これらの異常は,下層マントルの底辺に異常な物質特性があることを示している.
研究 の 目的:
- CMBにおける超低地震速度の原因となる物質の組成と安定性を調査する.
- 実験的観測を地震学的データと結びつける.
主な方法:
- ペロブスキート後のシリケート相の実験的合成と特徴付け.
- CMB条件をシミュレートする高圧,高温実験.
- 地震波の速度 (圧縮と切断) とプアソン比率の分析.
主要な成果:
- 40mol%までのFeSiO3を含むペロブスキート後のシリケート相は,CMB条件では安定しています.
- これらの鉄に富んだシリケートには,超低圧縮波と切断波の速度と高いポアソン比率があります.
- これらの相の形成は,コア-マントル反応によって可能である.
結論:
- 鉄に富んだペロブスキート後シリケートは,CMBで観測された超低速帯 (ULVZs) の妥当な説明である.
- マントルのダイナミクスは,この物質を集中させ,地震的に検出可能なパッチを作成することができます.
- この発見は,鉱物物理学の実験と,地球深層の地震学的観測を調和させるものである.
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