粘性弾性地球における潜水地震の変形サイクル
Kelin Wang1, Yan Hu, Jiangheng He
1Pacific Geoscience Centre, Natural Resources Canada, Geological Survey of Canada, Sidney, British Columbia V8L 4B2, Canada. kwang@nrcan.gc.ca
Nature
|April 21, 2012
まとめ
宇宙地質学は,マントルの粘度を明らかにし,地震の変形サイクルを制御し,潜水地帯の変形サイクルを制御する. 比較研究は,主要な地震の間の地殻運動の伝統的な弾性モデルを改訂する.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- テクトニクス (地質学) とは
- 地震学 地震学とは
背景:
- サブドクションゾーンは,地球で最も強力な地震を生成します.
- 宇宙地質学は,過去20年間で地震間の地殻変形の研究を変革しました.
- 現代の地質学的データは限られた期間をカバーしており,異なる潜水地帯の比較が必要である.
研究 の 目的:
- さまざまな潜水地帯からの地質データを統合する.
- 変形を制御する際の短期的および長期的マントル行動の相互作用を理解する.
- 地震変形の伝統的な弾性モデルに挑戦し,見直す.
主な方法:
- 宇宙ジオデシー技術を活用して地殻の変形を測定する.
- 地震周期の異なる時点での潜水地帯の比較分析を行うこと.
- 地質学的"スナップショット"を合成して,包括的な変形モデルを構築する.
主要な成果:
- 地震間変形は,短期 (数年) と長期 (数十年/数世紀) のマントルの粘度によって影響を受けます.
- サブダクションゾーンの変形の統一モデルが比較地質学研究から明らかになった.
- 鏡像としてコセイズミックとインターセイズミック変形を仮定する弾性モデルは,再評価されています.
結論:
- マントルの粘性は,潜水地帯における変形サイクルを調節する上で重要な役割を果たします.
- 地測量データの統合は,地質学過程のより微妙な理解を提供します.
- 将来の研究は,粘弾性マントルの振る舞いを組み込むモデルを改良し続けなければなりません.
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