Wilner Joel A, Nordin Bailey J, Getraer Alexander, Gregoire Rowan M, Krishna Mansa, Li Jiawen, Pickell Derek J, Rogers Emma R, McDannell Kalin T, Palucis Marisa C, Keller C
Department of Earth Sciences, Dartmouth College, 19 Fayerweather Hill Rd, Hanover, NH 03755, USA.
Department of Geoscience, University of Wisconsin-Madison, 1215 W Dayton St, Madison, WI 53706, USA.
Sci Adv. 2024 Dec 20;10(51):eadr2009. doi: 10.1126/sciadv.adr2009.
Earth's topography and climate result from the competition between uplift and erosion, but it has been debated whether rivers or glaciers are more effective erosional agents. We present a global compilation of fluvial and glacial erosion rates alongside simple numerical experiments, which show that the "Sadler effect," wherein geological rates show an inverse relationship with measurement timescale, comprises three distinct effects: a measurement thickness bias, a bias of erosion and redeposition, and a bias introduced by not observing quiescent intervals. Furthermore, we find that, globally, average glacial erosion rates exceed fluvial erosion rates through time by an order of magnitude, and that this difference cannot be explained by Sadlerian biases or by variations in hillslope, precipitation, or latitude. These findings support observations of increased erosion rates following Cenozoic cooling and glaciation, and reveal the importance of glacial erosion over millennial to orogenic timescales.
地球的地形和气候是隆升与侵蚀之间相互作用的结果，但关于河流和冰川谁是更有效的侵蚀营力一直存在争议。我们展示了一份全球河流和冰川侵蚀速率的汇编以及简单的数值实验，结果表明“萨德勒效应”（即地质速率与测量时间尺度呈反比关系）包含三种不同的效应：测量厚度偏差、侵蚀与再沉积偏差以及未观测到静止期所引入的偏差。此外，我们发现，从全球范围来看，随着时间推移，冰川的平均侵蚀速率比河流侵蚀速率高出一个数量级，而且这种差异无法用萨德勒偏差或山坡、降水或纬度的变化来解释。这些发现支持了关于新生代冷却和冰川作用后侵蚀速率增加的观测结果，并揭示了在千年至造山时间尺度上冰川侵蚀的重要性。
