ハワイのマウナ・ロア火山の深い裂け目の侵入によるストレス制御
Falk Amelung1, Sang-Ho Yun, Thomas R Walter
1Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, 4600 Rickenbacker Causeway, Miami, FL 33149, USA. famelung@rsmas.miami.edu
まとめ
マウナ・ロア火山は,深いマグマから膨らんでおり,ストレスの移転がマグマの蓄積を制御していることを示している. この発見は,火山の変形と噴火の可能性を理解するために極めて重要です.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- 火山学 火山学とは
- リモートセンシング (リモートセンサー)
背景:
- ハワイのマウナ・ロア火山は,浅い侵入と基礎地震による変形を示しています.
- 低層の火山の構造に広がる場所の位置づけは,まだ十分に理解されていない.
研究 の 目的:
- マウナ・ロアで変形を制御する地下過程を調査する.
- 火山の下部におけるマグマの蓄積メカニズムを理解するために.
主な方法:
- インターフェロメトリック合成開口レーダー (InSAR) のデータを使用した.
- 2002年から2005年にかけての変形パターンを分析した.
主要な成果:
- 南西断層地帯の,中程度の深さで堤防のようなマグマ体の長期膨張が検出されました.
- 以前は侵入や地震によって解き放たれた裂け目地帯の部分でのマグマの蓄積を観測した.
結論:
- 地下マグマの蓄積は,ストレス移転の影響を受けます.
- 浅い堤防の侵入と基礎地震は,マグマ経路と蓄積地帯を制御する役割を果たします.
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