ヒマラヤ山脈のオロゲンで同時にミオセンの延長と縮小
まとめ
ヒマラヤのオロゲン構造に不可欠な南チベット分離系は,19~2200万年前に活動していた. これは,地殻の拡張と収束がミオセンの重要な構造的プロセスであったことを示しています.
科学分野:
- 地質学 地質学 地質学
- テクトニクス (地質学) とは
- ジオクロノロジー (Geochronology) について
背景:
- 南チベット分離系 (STDS) は,ヒマラヤのオロゲンの変形核を上層から分離している.
- その発展は,地殻の加厚による重力潜在エネルギー差異と関連している.
研究 の 目的:
- ジオクロノロジックデータを用いてSTDSのアクティビティタイミングを調査する.
- ミオセンのヒマラヤ地殻構造における地殻の拡張と収束の役割を理解する.
主な方法:
- チベット南部のロングブック渓谷から採取した岩石サンプルを地理年代分析.
- 脱落活動と地殻の加厚現象の相関.
主要な成果:
- ジオクロノロジカルデータは,1900万年から2200万年前までのSTDSセグメントの活動を示しています.
- この時期は,より深い構造レベルでの地殻の著しい加厚と一致しました.
結論:
- STDSは,地殻の濃縮が顕著なミオセンの間隔で活性化していた.
- 上層地殻の拡大と下層地殻の収束の分離は,ヒマラヤの構造学において顕著であった.
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