2012年インド洋地震の観測から推論されたアステノスフィアのレオロギー
Yan Hu1,2, Roland Bürgmann1, Paramesh Banerjee3
1Berkeley Seismological Laboratory and Department of Earth and Planetary Science, University of California Berkeley, Berkeley, California, USA.
Nature
|October 11, 2016
まとめ
研究者達は 大規模なインド洋地震の後の 地震後の変形を研究し 海洋のアステノスフィアを理解しました 発見は,海洋プレートの下の薄い,低粘度なアステノスフィアの層を明らかにし,マントルのレオロジーにとって不可欠です.
科学分野:
- 地理学
- 構造物理学
- 地震学
背景:
- 海洋の殻の下にあるアステノスフィアの機械的性質は 十分に理解されていません
- 地震後の変形は上層マントルのレオロギーに洞察を与えますが,データは大陸の設定に制限されています.
- 大きな地震は裂け目から遠く離れた場所に 変形を引き起こし,その後に長期に渡る 地震後のリラックスが起こります
研究 の 目的:
- 地震後の変形データを用いて海洋マントルのレオロギーを制限する.
- アステノスフィアのメカニカル性質を調査する
- 大規模な海洋地震の後の粘着弾性緩解をモデル化するために.
主な方法:
- 連続的なグローバル・ナビゲーション・サテライト・システム・ステーションからの地質学的データの分析
- 三次元粘弾性有限要素モデルの開発と応用.
- 2012年インド洋地震後の地震後の変形をモデル化する.
主要な成果:
- 地震後のインド洋地域における水平の移転と垂直の上昇.
- 地質学的なデータは 地震後の大幅な緩和を示しています
- モデルには薄い (30〜200 km),低粘度なアステノスフィアが必要である.
結論:
- 観測された地震後の変形を説明するために,海洋石層の下にある薄い,低粘度のアステノスフィアの層は不可欠です.
- この研究は,海洋マントルのレオロギーの直接的な制約を提供します.
- 海のアステノスフィアの性質を理解することは,プレート構造とマントルのコンベクションモデルにとって鍵となるものです.
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