まとめ
西北太平洋のペラジック沈殿物は,盆地深化により,炭酸から深淵の粘土へと移行した. 地震プロファイルで特定されたこの面の境界線は,地質学的な時間における太平洋盆地全体の超越的な性質を示しています.
科学分野:
- 海洋地質学 海洋地質学
- 海洋学 海洋学 海洋学
- 堆積物学 堆積物学 堆積物学 堆積物学 堆積物学
背景:
- 西北太平洋の深淵地帯の床は,ジュラ紀末期からペラジック堆積物を受け取った.
- 堆積物のパターンは,盆地の深まりと海洋学的条件の変化とともに進化した.
研究 の 目的:
- 西北太平洋の深淵の床における歴史的堆積過程と面の変化を調査する.
- 炭酸から粘土沈殿への移行のタイミングと性質を特徴付ける.
主な方法:
- 沈殿面の境界を特定するために地震プロフィールの分析.
- フェイシス移行の年齢範囲を確立するための地質学的年代測定.
主要な成果:
- カーボネート堆積物がアビスカル粘土に取って代わられたことを示す,重要な表面の境界線が存在します.
- この境界は広範囲にわたるもので,西部の白亜紀中期から中央太平洋のオリゴセーンまで遡る.
- この境界線上およびその下には,チェルトが観察され,おそらくは堆積後のダイアゲネシスによって形成された.
結論:
- 盆地深化と侵襲的な地底水は,炭酸から粘土への沈着のシフトを促した.
- フェイシス境界の超越的な性質は,太平洋全体で進化する古海洋学的条件を反映しています.
- 堆積後の過程は,深淵の粘土の配列内のチェートの形成に重要な役割を果たしました.
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