中央太平洋と日本のガイオットのサンゴ礁の白期の沈没
Science (New York, N.Y.)
|April 26, 1974
まとめ
太平洋のギヨットや日本の海底山の真ん中白期のサンゴ礁は,アルビアン・ケノマニアン期における水没により,動物群の絶滅を経験した. この現象は,世界の海面上昇によって引き起こされた可能性が高い.
科学分野:
- パレオントロジー・パレオントロジー
- 海洋地質学 海洋地質学
- クレータ紀の平層図法
背景:
- ガイオットと海底山は,化石のあるサンゴ礁の構造を宿すことができる水中に潜った火山の島です.
- 中央太平洋の山脈と日本の海底山脈は,海洋古地理学の研究にとって重要な地域です.
- クレタ紀,特にアルビアン・ケノマン期は,海洋生態系の進化を理解する上で極めて重要です.
研究 の 目的:
- 太平洋のガイオットと日本の海底山脈のサンゴ礁の化石の年齢を決定するために.
- これらの白亜紀のサンゴ礁系における野生動物の絶滅の原因を調査する.
- 珊瑚礁の消滅と古海洋学的現象,特に海面の変化を相関させるため.
主な方法:
- 掘削されたサンゴ礁のサンプルから回収された化石の古生物学的分析.
- 絶滅イベントのタイミングを正確に特定するために,化石アセンブラージのストラティグラフィック・デッティング.
- リーフ構造の地質学的解釈とその古環境的文脈.
主要な成果:
- 発見された化石は,サンゴ礁が白亜紀中期に存在していたことを示している.
- サンゴ礁の動物は,アルビアン・ケノマニアン期に絶滅した.
- 証拠によると,サンゴ礁の死亡の主な原因は沈没である.
結論:
- これらのサンゴ礁の絶滅はアルビアン・ケノマニアン時代に起こった.
- ユスタティックな海面上昇によって引き起こされた可能性が高い沈没が,動物群の絶滅の原因であった.
- これらの発見は,白亜紀の古海洋学とサンゴ礁の生態系動態を理解するのに役立ちます.
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