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Updated: Jul 9, 2026

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Blast Quantification Using Hopkinson Pressure Bars
Published on: July 5, 2016
地震の速度と密度は,410キロメートルと660キロメートルの不連続度を越えてジャンプします
1Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093-0225, USA. Lawrence Livermore National Laboratory, Post Office Box 808, L-206, Livermore, CA 94551, USA.
まとめ
地震波の分析により,上部マントルの不連続性に関する新たな制約が明らかになった. 660キロメートルの不連続は,以前にモデリングされたよりも小さな密度ジャンプを示し,マントルのコンベクション研究に影響を与えています.
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
- 地球科学 地球科学 地球科学
背景:
- 410キロメートルと660キロメートルの不連続は,地球の上層マントルの重要なインターフェースです.
- これらの深さでの地震速度と密度の変化を理解することは,マントルの動力学にとって極めて重要です.
研究 の 目的:
- 平均的な地震速度と密度が410キロメートルと660キロメートルの不連続を飛び越えることを決定します.
- これらの値を,予備基準地球モデル (PREM) やピロライトマントルモデルなどの既存のモデルと比較する.
主な方法:
- 長期の地震波の到着の範囲依存をモデリングする.
- 410kmと660kmの断絶点からの地震波の反射を分析した.
主要な成果:
- 予備基準地球モデル (PREM) は410kmの不連続性には適合するが,660kmの不連続性には適合しない.
- ピロライトマントルのモデルは410kmの不連続性に一致しているが,660kmの反射を過剰に予測している.
- 660kmの不連続性における密度ジャンプは,PREMの9.3%よりも4〜6%低いと推定されています.
結論:
- 660kmの不連続性における密度ジャンプは,マントルのコンベクションモデルで一般的に使用されるよりも大幅に小さい.
- 改訂された地震速度と密度データは,上層マントルの構造と動態に関する私たちの理解を洗練します.
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