シーズモグラムのシーケンシング:コアマントルの境界領域における散乱のパノプティックビュー
1Department of Geology, University of Maryland, College Park, MD 20742, USA. dk696@cornell.edu.
まとめ
科学者たちは新しいアルゴリズムで 地震波を分析し 広範囲に広がる3D構造と 地球のコア・マントルの境界付近の 未知の超低速帯を明らかにしました
科学分野:
- 地質学と地震学
- 地球の深層構造と動態
背景:
- 地震波の散布は地表構造の洞察を提供しますが,局所分析に限られています.
- コアとマントルの境界は 地球の深い過程を理解するための 重要な領域です
研究 の 目的:
- 地震波の分散を総合的に分析するために,新しい多様学習アルゴリズム"シーケンサー"を開発し,適用する.
- パシフィック地域の核-マントルの境界で散乱現象のパノプティックな視点を得るために.
- 地震波の伝播に影響を与える3次元構造を特定し,特徴づけること.
主な方法:
- 核-マントルの境界に沿って波の数千の地震グラフの同時分析.
- マニフォールド学習アルゴリズム ("シーケンサー") を無監督のパターン検出に適用する.
- 振動波の波形の中で分散した地震波の到着を特定する.
主要な成果:
- 3次元構造によって散らばった地震波が 分析された波の半分近くで検出されました
- 太平洋の真ん中にある 横断的な異質性を明らかにした
- ハワイの下の 羽根と マルキース諸島の下の 未確認の超低速圏を特定した
結論:
- コア・マントルの境界は広範囲の横向的な異質性を示し,以前の局所的な見解に挑戦しています.
- "シーケンサー"アルゴリズムは 地球の深部探査のための 強力な無監視の方法を提供します
- マントルの羽根と超低速帯を含む 地球の深い構造に関する新しい洞察が 発見されました
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