板块构造学和地幔流动的动态:从局部到全球规模
Georg Stadler1, Michael Gurnis, Carsten Burstedde
1Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, TX 78712, USA.
Science (New York, N.Y.)
|August 28, 2010
概括
高分辨率的全球地幔流动模型揭示了板块构造学是如何被板块边界的力量所驱动的. 这项研究表明,板块下降如何影响地球上的板块运动和消散.
科学领域:
- 地质物理学 地质物理学
- 构造物理学 构造物理学
- 计算地力学计算地力学
背景情况:
- 板块构造学受到板块边界的力量的支配,但高分辨率的全球地幔流动模型在计算上具有挑战性.
- 了解这些力量需要详细的模拟地幔对流和板块相互作用.
研究的目的:
- 开发和利用高分辨率的全球地幔流动模型来研究板块构造学的动态.
- 解决单个板边缘到1公里为前所未有的模型准确性.
主要方法:
- 在并行计算架构上使用自适应网状精细化算法.
- 将板块运动纳入全球地幔流动模拟.
- 在1公里尺度上解决了单个板边缘.
主要成果:
- 后弧延伸和板块回滚被确定为板块上层地幔下降的新出现的后果.
- 下层地幔的冷热异常通过狭窄的高粘度板块影响海洋板块的速度.
- 石灰岩层内的粘性消散在沟中占石灰岩层和地幔总消散的5-20%.
结论:
- 先进的计算方法使全球地幔流和板块构造学的高分辨率建模成为可能.
- 薄板动力学显著影响地球地幔内的板块运动和能量消散.
- 这项研究为推动板块构造和地幔动态的力量提供了关键的见解.
相关概念视频
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01:17Steady, Laminar Flow Between Parallel Plates
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01:23Introduction to Types of Flows
Fluid flows are categorized by dimensionality and behavior, with one-dimensional flow being the simplest form, where properties like velocity and pressure change only along a single axis. Water moving through straight pipes exemplifies this flow type, as variations in other directions are minimal. One-dimensional analysis helps simplify understanding such flows, focusing solely on changes along the pipe's length.
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01:22Eulerian and Lagrangian Flow Descriptions
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01:22Couette Flow
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01:24Turbulent Flow
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