The stratal types composing aeolian dunes preserve a record of the transport and sorting of grains and are categorized into: 1) grainflow strata, 2) grainfall laminae, and 3) wind-ripple laminae. The arrangement of these deposits in the cross beds of a formative dune is largely unexplored. Here, field results from White Sands Dune Field, New Mexico, USA, are used to test the hypothesis that dune height controls the arrangement, abundance, and geometry of cross-stratification types. Grainflow thicknesses and deposit widths were measured on wind-scoured stoss-side exposures of seven crescentic dunes with heights ranging from 1.7 m to 11.2 m. Dozens of grainflow thickness measurements were taken along transverse-oriented strata normal to the crest on each dune. The results show that grainflow thickness averages from 1 cm to 4 cm. These data show a positive trend between mean grainflow thickness and dune height but only for the grainflow thicknesses measured at the bases of dunes. The tallest dune (11.2 m) produced many thick grainflow packages of 10 cm to 30 cm in which individual grainflow strata were indistinguishable from each other. This amalgamation was also found to be characteristic of larger dunes—the product of a lack of grainfall deposits separating individual grainflows. These differences in grainflow strata at the bases of dune lee slopes are linked to the temporary storage of sediment along the upper parts of lee slopes. In taller dunes with longer lee slopes, amalgamated grainflows which require multiple avalanche events and take longer time to reach the base transport temporarily stored sediment at upper parts of the slope. This allows time for wind ripples to rework accumulations near the base, where grainfall deposition is also limited. Shorter dunes lack this temporary storage mechanism, as individual grainflows can move across the entire lee slope in a single event, and grainfall accumulates across the entire lee slope. These stratigraphic measurements and process-based understanding will be useful in estimating original dune height in ancient cross-strata and will lead to a better interpretation of aeolian stratigraphy.

中文翻译：

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跨层建筑上的风沙丘高度控制：美国新墨西哥州白沙丘沙丘场

构成风沙丘的地层类型保留了谷物运输和分类的记录，分为以下类别：1）颗粒流地层，2）颗粒状薄层和3）风波纹薄层。这些沉积物在形成沙丘的横床中的排列方式很大程度上未被探索。在这里，美国新墨西哥州白沙丘沙丘油田的田间结果用于检验以下假设：沙丘高度控制交叉分层类型的排列，丰度和几何形状。在风蚀的7个新月形沙丘的草丛侧面进行了测量，测得了谷粒厚度和沉积物宽度，其高度范围为1.7 m至11.2 m。沿垂直于每个沙丘波峰的横向地层进行了数十次颗粒流厚度测量。结果表明，颗粒流厚度平均为1 cm至4 cm。这些数据显示了平均谷粒流厚度和沙丘高度之间的正趋势，但仅针对在沙丘底部测得的谷粒流厚度。最高的沙丘（11.2 m）产生了许多厚的10 cm至30 cm的谷物流包裹，其中各个谷物流地层彼此无法区分。还发现这种合并是较大的沙丘的特征-缺乏分离单个谷物流的谷物沉淀物的产物。沙丘背风斜坡底部的流层差异与沿背风斜坡上部的沉积物的临时存储有关。在较高的沙丘和更长的背风坡度下，需要进行多次雪崩事件并需要较长时间才能达到基本运输的混合谷物流，这些沉积物临时存储在坡度的上部。这样可以留出一定的时间，使风浪重新加工底部附近的堆积物，而底部的颗粒物沉积也受到限制。较短的沙丘缺乏这种临时存储机制，因为单个谷物流可以在一次事件中在整个背风处移动，并且谷物堆积在整个背风处积聚。这些地层测量和基于过程的理解将有助于估算古代跨层中的原始沙丘高度，并将有助于更好地解释风成地层。