地球の内核が溶けていく
David Gubbins1, Binod Sreenivasan, Jon Mound
1School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK.
Nature
|May 20, 2011
まとめ
地球のコアのダイナミクスは局所的な融解を引き起こし,内部コアの上の地震異常層を潜在的に説明する可能性があります. ジオダイナモシミュレーションは,コアプロセスと地震シグネチャーに影響を与える熱流の変動を明らかにします.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- 地球科学 地球科学 地球科学
- 計算物理学の物理
背景:
- 地球の磁場は,液体鉄核のダイナモの作用から発生します.
- 核のコンベクションは,内核の凍結時に冷却と光元素の放出によって引き起こされます.
- マントルのコンベクションは,コアからの熱抽出における重要な横向の変動を引き起こす.
研究 の 目的:
- コア・マントル境界における横の熱流の変化が内核に与える影響を調査する.
- 内核内の局所的な融解の可能性を調査する.
- 内核の上の変数組成層の存在を説明するために.
主な方法:
- ジオダイナモシミュレーションを利用した.
- 分析された熱流は内核の境界まで伝達される.
- 局所的な融解と凍結のモデル化された効果.
主要な成果:
- ジオダイナモのシミュレーションでは,横の熱流の変動により,熱が内核に流れる可能性があることが示されています.
- この内側への熱流は,内核の境界で局所的な融解を誘導する可能性があります.
- 融解は重い液体を放出し,観測された地震異常層を形成する可能性がある.
結論:
- 局所的な融解は,内核の上の変数組成層の単純な説明を提供します.
- このメカニズムは,内核の行動に関する複雑な仮定の代替案を提供します.
- 局所的な融解と凍結は,内核そのものの内部で強い地震異常を生成することができます.
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