まとめ
地震波は,シエラネバダ山脈の下にある高速の岩層を明らかにし,おそらく古代のオフィオライト板である. この層は,ネバダの試験場から波の移動時間が速くなり,シエラ根がマントルの奥深くまで広がっていることを示している.
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
- テクトニクス (地質学) とは
背景:
- シエラネバダ全域における地震波の伝播は,方向的な異常を示している.
- 説明がつかない観測は,ネバダの試験場から地震波がより早く到着していることです.
研究 の 目的:
- シエラネバダを横断する異常な地震波の移動時間の原因を調査するために.
- シエラネバダ山脈の深い構造を決定するために.
主な方法:
- 地震や爆発を含む様々な源からの地震波の移動時間の分析.
- 地震データを解釈し,地下構造を推論するための地球物理モデリング.
主要な成果:
- 地震波はネバダの試験場を除くすべての方向から遅延で到着します.
- ネバダの試験場から到着した初期の波は,高速の岩層を通って浮上することを示唆しています.
- この高速度層は,潜水したオフィオリート板であると考えられています.
- シエラ山脈の根は,マントルに約55キロの深さまで広がっています.
結論:
- 沈殿したオフィオライト板は,シエラネバダの下の高速層を形成する可能性があります.
- シエラネバダ山脈の深い構造には,マントルに大きく広がる根が含まれています.
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