通过爆发洪水逐渐切割道地
Isaac J Larsen1,2, Michael P Lamb2
1Department of Geosciences, University of Massachusetts, Amherst, Massachusetts 01003, USA.
Nature
|October 14, 2016
概括
灾难性的洪水在地球和火星上造成了峡谷. 新的研究表明,考虑到侵蚀值,洪水排放量比以前估计的小5-10倍,影响了行星表面的修改和气候变化的理解.
科学领域:
- 地形学
- 星球科学
- 水文学
背景情况:
- 星球表面,包括地球和火星, 具有由灾难性的爆发洪水形成的大岩.
- 估计洪水的大小对于了解行星表面的变化,早期火星水文和气候变化至关重要.
- 目前的洪水排放估计通常假定峡谷被填满,但另一个假设考虑侵蚀值.
研究的目的:
- 为了调查峡谷形成的洪水排放估计.
- 测试峡谷形态在切割过程中适应侵蚀值的假设.
主要方法:
- 考虑基石侵蚀门的峡谷切口模型.
- 模型结果与"全面"的洪水估计进行了比较.
- 分析了莫西斯·库利的石流深度指标.
主要成果:
- 考虑到侵蚀值,几乎不变的排放量比Moses Coulee的全边估计低5-10倍.
- 这些较低的排放与石杆流深指标保持一致.
- 全边型号预测了冰川湖爆发洪水的不切实际,单调增长的排放量.
结论:
- 在破碎的岩石中被洪水雕刻的景观可能达到基石侵蚀的门状态.
- 这意味着洪水排放量远低于之前的推断.
- 对地球和火星的灾难性洪水动态和景观演变的理解进行了修订.
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