放射的相関関数に基づく地震地球構造とマントル流動モデルの比較
Science (New York, N.Y.)
|September 10, 1993
まとめ
数学的シミュレーションは,マントルの移行領域の障壁が温度パターンを生み出していることを示しているが,地震データは,この分層化が大規模なマントルのコンベクションに影響する証拠を欠いている.
科学分野:
- 地質物理学 地質物理学とは地質物理学です.
- 地球科学 地球科学 地球科学
- コンピューティング・モデリング
背景:
- マントルのコンベクションはプレート構造と熱分布を駆動する.
- 中間マントルの移行ゾーンには,化学的または相変化の障壁が含まれている可能性があります.
- これらの障壁を理解することは,マントルダイナミクスにとって極めて重要です.
研究 の 目的:
- マントルのコンベクションに対する移行ゾーンバリアの影響を調査する.
- 数値シミュレーション結果を地震トモグラフィーデータと比較する.
- マントルの大規模な流れに対する層分化の影響を評価する.
主な方法:
- マントルのコンベクションの3次元数値シミュレーション.
- 化学的またはエンド熱的相変化による流動阻力モデリング.
- 温度場の分析と地震切断速度モデルとの比較.
主要な成果:
- シミュレーションは,課された障壁の垂直温度相関長さの明確な最小値を明らかにします.
- この機能は,フィルタリングされたデータであっても持続し,強度を示します.
- 地震トモグラフィーデータは,そのような特徴の明確な証拠を示さない.
結論:
- 中部マントルの移行地帯の層化は,大規模なマントルの循環に限られた影響を及ぼします.
- モデルと地震データとの不一致は,バリアが地球マントルの流れを大幅に妨害しないことを示唆している.
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