概括
天然和合成石英石通过牛顿位移 (哈珀-多恩) 变形,在高温和低应力下爬行. 这表明,地的下层可以以粘性液体的形式在比以前想象的更低的压力下通过脱位机制流动.
科学领域:
- 地质地质地质地质地质地
- 材料科学 材料科学 材料科学
- 固体地球地质物理学 地质物理学
背景情况:
- 了解地下层的浮力学对于板块构造学和地震解释至关重要.
- 之前的模型通常假定在较低地岩中的性流动的应力门较高.
研究的目的:
- 为了研究下层地条件下石英石的变形机制.
- 确定在相关的温度和应力下,石英石中是否发生牛顿位移 (哈珀-多恩) 爬行.
主要方法:
- 自然和合成石英样本的机械测试.
- 微结构分析以确定变形特征.
- 模拟高温 (>1073 K) 和低应力 (<300 MPa) 的实验条件.
主要成果:
- 天然和合成的石英石都显示出牛顿位移 (哈珀-多恩) 爬行的证据.
- 这种爬行机制在超过1073K的温度和低于300MPa的应力下观察到.
结论:
- 在较低地的条件下,石英可以通过哈珀-多恩爬行变形.
- 下层地可能会像牛顿粘性流体一样表现,压力远低于以前的假设,由位移机制驱动.
相关概念视频
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If...
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