2011年の東北大震災の下心地の上での移転
Mariko Sato1, Tadashi Ishikawa, Naoto Ujihara
1Hydrographic and Oceanographic Department, Japan Coast Guard, 5-3-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan. eisei@jodc.go.jp
Science (New York, N.Y.)
|May 21, 2011
まとめ
2011年の東北大震災は,海底の大規模な移動を引き起こし,水平の動きは20メートルを超え,震源地近くの垂直の上昇が顕著でした. これらの発見は,メガ・スラスト・イベント中に前例のない海底地質学的なシフトを明らかにしています.
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
- 海洋学 海洋学 海洋学
背景:
- 2011年の東北大震災は,日本の海岸沖のマグニチュード9.0のメガプルスイベントでした.
- 海底の変形を理解することは,地震リスクの評価に不可欠です.
研究 の 目的:
- 2011年の東北大震災に関連した海床の移動を定量化するために.
- 海底の動きと地上の観測を比較する.
主な方法:
- グローバル・ポジショニング・システム (GPS) と音響データを組み合わせた分析.
- 地震の焦点地域における海底の動きの直接検出.
主要な成果:
- 20メートルを超える広範囲の水平の海底移動が検出され,陸上の移動よりも大幅に大きい.
- 測定された最大水平移動は,東南方向で約24メートルです.
- 海底の垂直上昇が3メートル近く観測され,沿岸の沈下と対照的であった.
結論:
- 2011年の東北大震災は,海底の異常に大きな移動を引き起こした.
- 海底の変形パターンは,陸上で見られたものとは大きく異なっていた.
関連する概念動画
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