在一个冷却的气候下,山脉侵蚀在全球范围内加速
Frédéric Herman1, Diane Seward2, Pierre G Valla1
11] Institute of Earth Sciences, University of Lausanne, CH-1015 Lausanne, Switzerland [2] Department of Earth Sciences, Swiss Federal Institute of Technology, Sonneggstrasse 6, CH-8092 Zürich, Switzerland.
Nature
|December 20, 2013
概括
全球山脉侵蚀率显著增加,特别是在200万年前以来. 这种上升,在冰川地区最明显,表明气候冷却和冰川加速侵蚀和沉积物流动.
科学领域:
- 地球科学 地球科学 地球科学
- 地质地质地质地质地质地
- 气候科学 气候科学
背景情况:
- 气候显著影响地球表面的侵蚀过程.
- 晚凯诺纪冷却和北半球冰期对全球侵蚀速度的影响尚不清楚.
- 挑战包括解释沉积物记录和区分构造学与气候侵蚀贡献.
研究的目的:
- 量化全球侵蚀速度及其时间变化.
- 调查气候冷却和冰川对山地侵蚀的影响.
- 为了评估全球沉积物流动数百万年来的变化.
主要方法:
- 全球18000个岩石基层的热度计年龄的汇编.
- 应用一个正式的反转程序来估计侵蚀率.
- 在地质时间尺度上的沉积物源区域的侵蚀量化.
主要成果:
- 自大约600万年前以来,山地侵蚀速度有所增加,自200万年前以来加速速度最快.
- 在全球范围内观察到侵蚀率的增加,但在冰川山脉中最为显著.
- 结果表明,冰川过程在增强侵蚀方面起着重要作用.
结论:
- 全球山脉侵蚀和沉积物流量增加,与世-普世冷却和冰川化相吻合.
- 冰川过程是增加山区侵蚀率的关键驱动因素.
- 这些发现提供了关于气候和地球表面过程之间的长期合的见解.
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