グーテンベルクの不連続性:石層とアステノスフィアの境界で溶ける
1Department of Terrestrial Magnetism, 5241 Broad Branch Road, NW, Washington, DC 20015, USA. nschmerr@dtm.ciw.edu
Science (New York, N.Y.)
|March 24, 2012
まとめ
海洋の下にあるグーテンベルク不連続性 (G) は,石層の底部の部分的な融解によって引き起こされる可能性があります. この地震信号は,上流と下流などのマントルダイナミクスによって強化されます.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- 地震学 地震学とは
- マントラダイナミクス マントラダイナミクス
背景:
- リトスフィア-アステノスフィアの境界線 (LAB) は,硬いプレートとコンベクトマントルを分離しています.
- LABにおける地震的不連続性であるグーテンベルク不連続性 (G) の起源は十分に理解されていません.
研究 の 目的:
- 海洋プレートの下にあるグーテンベルク不連続 (G) の原因を調査するために.
- 石灰圏-アステノスフィアの境界 (LAB) で部分的に溶けるかどうかを決定するには,G反射性を説明します.
主な方法:
- 高周波SS前駆者の地震データの分析.
- 太平洋プレートの下40~75kmの深さで,負の速度コントラストとしてGの断続的な検出.
主要な成果:
- Gは, LABの近く,火山活動と溶融生産の地域で観察されます.
- 観測結果は,石層の底部で断続的なアステノスフィアの部分融解層と一致しています.
結論:
- グーテンベルク不連続性 (G) は,おそらく,石層とアステノスフィアの境界 (LAB) の部分的な融解の結果である.
- 融解の生成は,マントルの上流,小規模なコンベクション,そして潜水中の流体放出によって強化されます.
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