欧洲的长期实力及其对板材成型工艺的影响
1Department of Earth Sciences, University of Oxford, South Parks Road, Oxford OX1 3PR, UK. martap@earth.ox.ac.uk
Nature
|July 22, 2005
概括
大陆坑比较年轻的构造学省份更强大. 这项研究协调了测量石质层强度 (有效弹性厚度,Te) 的方法,揭示了古老的石坑比年轻的区域具有显著的Te.
科学领域:
- 地质物理学 地质物理学
- 构造学 构造学 构造学 构造学
- 地球科学 地球科学 地球科学
背景情况:
- 大陆变形集中在年轻的构造学省份,这表明坑更强.
- 古代和法内罗纪石质层的相对强度,这是构造变形的关键因素,仍在争论中.
- 有效弹性厚度 (Te) 是石质层强度的代理,但存在空间变化和测量差异.
研究的目的:
- 通过使用两个不同的方法的一致配方,估计整个欧洲有效弹性厚度 (Te) 的变化.
- 调和从"布格尔连贯性"和"空气入口"方法中获得的不同Te估计值,特别是在形区域.
- 为了研究石质层强度 (Te) 和地质年龄之间的关系.
主要方法:
- 应用了"布格尔连贯性"和"空气入口"方法来估计在欧洲的有效弹性厚度 (Te).
- 确保了两种方法的一致配方,以便直接比较结果.
- 估计的Te值与地质年龄和区域地质相关联.
主要成果:
- 当一致制定时,这两种方法都产生了与地质省份相关的可比Te值.
- 旧的石质层 (≥ 1.5 Gyr) 与较年轻的石质层 (平均 Te < 30 km) 相比,表现出明显更大的强度 (平均 Te > 60 km).
- 通过一致的配方,先前研究的方法之间的差异,特别是对克拉顿的方法,可以减少.
结论:
- 石质层的强度强烈地取决于地质年龄,古老的坑比年轻的省份强得多.
- 观察到的强度差异归因于石板结构的进化变化,包括厚度,地热梯度和组成.
- 在地球历史上,地幔温度和挥发性物质含量的下降很可能影响了这些结构变化,并导致了岩层强度的变化.
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