Low-relief plateaus separated by deeply incised fjords are hallmarks of glaciated, passive continental margins. Spectacular examples fringe the once ice-covered North Atlantic coasts of Greenland, Norway and Canada, but low-relief plateau landscapes also underlie present-day ice sheets in Antarctica and Greenland. Dissected plateaus have long been viewed as the outcome of selective linear erosion by ice sheets that focus incision in glacial troughs, leaving the intervening landscapes essentially unaffected. According to this hypothesis, the plateaus are remnants of preglacial low-relief topography. However, here we use computational experiments to show that, like fjords, plateaus are emergent properties of long-term ice-sheet erosion. Ice sheets can either increase or decrease subglacial relief depending on the wavelength of the underlying topography, and plateau topography arises dynamically from evolving feedbacks between topography, ice dynamics and erosion over million-year timescales. This new mechanistic explanation for plateau formation opens the possibility of plateaus contributing significantly to accelerated sediment flux at the onset of the late Cenozoic glaciations, before becoming stable later in the Quaternary.

中文翻译：

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冰川大陆边缘高原景观的形成

由浅切的峡湾隔开的低起伏高原是冰川化的被动大陆边缘的标志。壮观的例子在曾经被冰雪覆盖的格陵兰，挪威和加拿大的北大西洋海岸边缘，但是低浮雕的高原景观也构成了当今南极洲和格陵兰的冰盖的基础。长期以来，被解剖的高原一直被认为是冰盖选择性地线性侵蚀的结果，冰盖将切口集中在冰川槽中，而中间的地貌基本上没有受到影响。根据该假设，高原是冰川前低浮雕地形的残余。但是，这里我们使用计算实验来证明高原像峡湾一样，是长期冰盖侵蚀的新兴性质。冰盖可以根据底层地形的波长增加或减少冰川下的浮雕，而高原地形则是由地形，冰动力学和侵蚀之间数百万年时间尺度上不断变化的反馈动态产生的。高原形成的这种新的机理解释为高原在新生代末期冰川开始时对加速泥沙通量做出显着贡献的可能性提供了可能性，之后在第四纪后期变得稳定。