ハワイのホットスポットの下にあるマントルの剪定波速度構造
Cecily J Wolfe1, Sean C Solomon, Gabi Laske
1Hawaii Institute of Geophysics and Planetology, University of Hawaii at Manoa, Honolulu, HI 96822, USA. cecily@soest.hawaii.edu
まとめ
地震画像は,ハワイのホットスポットの下にある深いマントルの羽根を明らかにしています. この高温の上流は下層マントルから発生し,島鎖の構造に影響を与えます.
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:
- 海洋のホットスポットの下にあるマントルの構造を理解することは,それらの起源の深さを決定するために不可欠です.
- ハワイ諸島は火山のホットスポットの典型的な例です.
研究 の 目的:
- ハワイ諸島の下にある3次元マントルの構造を定義する.
- ハワイのホットスポットの熱異常の深さと範囲を調査するために.
主な方法:
- 海底と陸上の地震計のネットワークを使用して,地震シーア波速度データを取得する.
- SKS (シェア波分裂) の観測を統合して,地震の解像度をさらに深さまで拡大する.
主要な成果:
- ハワイ島連鎖に沿って伸びた上部マントルの低速度異常の特定.
- 周囲のパラボリックの高速度異常の観測.
- マントルの移行地帯 (深さ410660 km) まで広がる低速度が確認され,薄くなりつつある.
- ハワイの下と南東の広大な低速度領域が,深さ1500kmまで検出されました.
結論:
- 地震画像は,ハワイのホットスポットが,下層マントルから上向きに湧き上がる高温の羽根によって作動していることを強く示唆しています.
- 観測された構造は,ハワイのホットスポットの深い起源の証拠を提供します.
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