接地区对冰架内部结构的影响
K E Miles1, B Hubbard2, A Luckman3
1Lancaster Environment Centre, Faculty of Science and Technology, Lancaster University, Lancaster, UK. k.miles1@lancaster.ac.uk.
Nature communications
|May 12, 2025
概括
研究人员在南极洲发现了一个新的中间冰单元.
科学领域:
- 冰川学的冰川学
- 南极冰架的动态 南极冰架的动态
- 冰芯分析 冰芯分析
背景情况:
- 南极冰架由大陆流星冰,现场流星冰和海洋冰组成.
- 了解冰架基底过程对于预测冰损失至关重要.
研究的目的:
- 为了识别和描述Larsen C冰架内以前未被识别的冰块.
- 为了确定这个新冰块的形成机制和位置.
主要方法:
- 钻孔光学电视监视器记录记录以分析冰层结构和结构.
- 流线建模以模拟冰流并推断形成条件.
主要成果:
- 在大陆冰和现场石冰之间,发现了一块几十米厚的中间冰块.
- 这个单元呈现出层次,深度随着深度的逐渐增加 (~60°).
- 它的平分层位置和深度表明它是在接地区形成的.
结论:
- 中间冰块可能是由于变化的表面斜率和接地区域的强烈变形而形成的.
- 这个单元的顶部可以作为在南极冰架上接地区域冰深度的标记.
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