最後の2つの氷河期間の水熱活動の増加
D C Lund1, P D Asimow2, K A Farley2
1Deptartment of Marine Sciences, University of Connecticut, Groton, CT 06340, USA.
Science (New York, N.Y.)
|January 30, 2016
まとめ
氷床にフィードバックを与える可能性があります. 氷河期間の熱水活動の増加は,マントルの融解が脱氷を促したことを示唆している.
科学分野:
- 地球科学
- 地質学
- 海洋学
背景:
- 海底の広がりとマントルの圧縮解消により生じるマグマチズム.
- 融解は氷河期と氷河期間の海面の変化によって変化し,マグマ流と氷床の大きさを結びつける可能性があります.
- プレイストセンの気候変化とマグマティズムを 結びつけるための正確なタイミングは ありませんでした
研究 の 目的:
- 過去の気候変動との関係を調査する
- 溶融の変動のタイミングを制限する
- 氷河周期におけるフィードバックメカニズムとしてのマグマ流の潜在的役割を調査する.
主な方法:
- イースト・パシフィック・ライズの 年代付けされた堆積物の分析
- 過去の熱水活動レベルを再構成する.
- 氷河期と氷河間期との相関関係
主要な成果:
- 過去2つの氷河期間の水熱活動が 増えたことを示しています
- 異常な上層マントルの融解は,海面が低かった氷河期に起きたという証拠がある.
- 氷河解凍の時期と重なった
結論:
- 氷河期間の海面変動は上層マントルの溶け方と海中山脈のマグマティズムに影響する.
- 氷河解凍の過程で増えたマグマティズムは,熱と炭素の放出によって氷床の退却に寄与した可能性がある.
- 氷床の大きさに負のフィードバックを与え,地球的な気候変動に影響を与える可能性があります.
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