地球の不連続な化学層を660キロの境界地形から推論する
Wenbo Wu1,2,3, Sidao Ni4, Jessica C E Irving2
1State Key Laboratory of Geodesy and Earth's Dynamics, Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China.
まとめ
地震波を用いて 660キロメートルの境界で 重要な地形図を発見しました この発見は 化学的層構造と 不完全なマントルの循環を示唆しています
科学分野:
- 地理学
- 地震学
- 固体地球力学
背景:
- 地球の内部ダイナミクスを理解するには,マッピングインターフェースのトポグラフィに依存します.
- 660キロメートルの境界線が上層と下層のマントルを分離し,その大規模な地形はよく研究されています.
- この境界での小規模な地形測定は困難です.
研究 の 目的:
- 660キロの境界の 小規模な地形を調査する
- マントルの構造とダイナミクスに対する観測された地形の影響を調査する.
主な方法:
- 散らばったP'P'地震波の分析
- 短距離スケールの地形変化をマッピングする.
主要な成果:
- 特定の地域における660キロメートルの境界線で重要な短距離地形が検出されました.
- 化学的層付けと相関する高度の短スケール粗さ.
- 410キロメートルの境界線で比較可能な小規模な地形は観察されなかった.
結論:
- 化学層が660キロの境界にあることを 裏付けています
- 観測により,地球の上層と下層の間の循環は部分的に遮断されたり,不完全であったりしています.
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