まとめ
アラスカの白亜紀の渦岩は,古代の海底の溝に堆積していたことを示している. この地質学的な特徴は,後になって,第3期初期に,近代のアレウチア・アーチ・トレンチ・システムに置き換えられた.
科学分野:
- 地質学 地質学 地質学
- パレオントロジー・パレオントロジー
- テクトニクス (地質学) とは
背景:
- クレタ紀の渦岩は,アラスカ大陸の縁とベーリング棚の縁に沿って露出しています.
- これらの堆積物は1700キロメートルに広がり,重要な地質学的特徴を示しています.
研究 の 目的:
- アラスカの白紀の泥岩の堆積環境を解釈する.
- クレタ紀の溝から第三期のアレウチアの弧溝への構造的移行を理解するために.
主な方法:
- コンチネンタルマージンに沿ったタービダイト曝露の分析.
- 古流動の流れパターンの調査.
- 火山の破片の構成の識別と分析.
主要な成果:
- トルビダイトの堆積は,海洋のの設定で発生しました.
- 古代時代のデータによると,大陸の縁まで平行流が流れていたことが示唆されている.
- 豊富なアンデシート火山の破片は,火山の源泉を示しています.
結論:
- アラスカの白期の大陸の縁は,海洋の溝と接していた.
- この溝は,その後,第3期初期にアレウティアン・アーチ・トレンチ・システムに取って代わられました.
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