Linear dunes are the most common type of dune found on Earth and exist on several extra‐terrestrial bodies, but despite this abundance their internal stratigraphy has not been commonly agreed. A cellular automaton is deployed to simulate the development of linear dunes, starting from a flat bed, under bi‐modal oblique wind regimes of varying degrees of asymmetry. The internal stratigraphy of the linear dunes is monitored by keeping track of (buried) erosion surfaces, avalanche deposits and vertical accumulation, as well as the age of last subaerial exposure of the sediments. The simulations show the initial pattern‐coarsening of a network of small dunes into fewer larger longitudinal ridges via bedform interactions and Y‐junction dynamics. Three newly recognized types of bedform interaction are identified that relate to initial Y‐junction dynamics: longitudinal crest‐splitting, which creates free dune tips that can interact with adjacent dunes, and laterally oscillating interactions that lead to ephemeral Y‐junctions (normal or reverse). The results show that these three bedform interactions leave no persistent signatures in the stratigraphic record. However, a further three bedform interactions involving the superposition of one dune onto another – merging, cannibalizing and repulsion (known from transverse dune field dynamics) – do leave specific evidence in the internal stratigraphy of the remaining dune, a buried interaction surface at a specific inclination. The preservation potential of this interaction surface varies between the three types. After the initial pattern‐coarsening phase, the linear dunes become larger and more independent and their crest orientation follows the net resultant transport direction. The stratigraphies of mature dunes under wind regimes of differing asymmetry show that under (nearly) symmetrical winds the dune accumulates mainly vertically, with strata dipping parallel to the flanks, while under more asymmetrical wind regimes the internal stratigraphy resembles that of transverse dunes.

中文翻译：

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用细胞自动机模拟线性沙丘的内部沉积结构

线性沙丘是在地球上发现的最常见的沙丘类型，并存在于几个地面物体上，但是尽管如此，线性沙丘的内部地层学尚未得到普遍认可。部署了蜂窝自动机以模拟线性沙丘的发展，该线性沙丘从平板开始，在不对称程度不同的双峰斜风下。线性沙丘的内部地层是通过跟踪（埋藏的）侵蚀面，雪崩沉积物和垂直堆积以及沉积物最后一次暴露在空中的年龄来监测的。仿真显示，通过床形相互作用和Y轴连接动力学，小沙丘网络的初始模式粗化为较少的较大纵向脊。确定了与初始Y轴动力学有关的三种新认识的床形相互作用类型：纵向波峰劈裂，产生自由的沙丘尖端，可以与相邻的沙丘相互作用，以及横向振荡的相互作用，导致短暂的Y形结（正向或反向）。结果表明，这三种岩床相互作用在地层记录中没有留下持久的特征。但是，涉及沙丘到另一沙丘的叠加（合并，自相咬合和排斥）的另外三种床形相互作用（从横向沙丘场动力学已知）在剩余沙丘的内部地层学中确实留下了特定的证据，即在特定位置的掩埋相互作用表面倾角。该相互作用表面的保存潜力在三种类型之间变化。在初始图案粗化阶段之后，线性沙丘变得更大且更独立，并且其波峰方向遵循最终的净运输方向。成熟的沙丘地层在不同的不对称风况下显示，在（几乎）对称风下，沙丘主要垂直堆积，地层平行于侧翼倾斜，而在非对称风况下，内部地层类似于横向沙丘。