Recognition and interpretation of sedimentary structures is fundamental to understanding sedimentary processes. Banded sandstones are an enigmatic sedimentary facies comprising alternating mud-rich (as matrix and/or mud clasts) and cleaner sand layers. The juxtaposition of hydrodynamically different grain sizes contradicts established models of cleaner-sand bedform development. Here, outcrop, subsurface core, and petrographic data from three deep-water systems, with well-constrained paleogeographic contexts, are used to describe the range of sedimentary textures, bedform morphologies, and facies associations, and to quantify the mud content of banding. Banding can occur in any part of a bed (base, middle, or top), but it typically overlies a structureless basal sandstone or mud-clast conglomerate lag, and is overlain by clean parallel-laminated sandstone and/or ripple cross-lamination. Banding morphology ranges from sub-parallel to bedforms that comprise low-angle laminae with discontinuous lenses of mudstone, or asymmetric bedforms comprising steeply dipping foresets that transition downstream into low-amplitude bedwaves, or steeply dipping ripple-like bedforms with heterolithic foresets. This style of banding is interpreted as a range of bedforms that form progressively in the upper-stage plane-bed flow regime via tractional reworking beneath mud-laden transitional plug flows. The balance of cohesive and turbulent forces, and the rate of flow deceleration (aggradation rate), govern the style of deposit. Banded sandstones and linked debrites are rarely found juxtaposed together in the same bed because they are distributed preferentially in proximal and distal settings, respectively. Understanding the origins of banding in turbidite sandstones, the conditions under which it forms, and its distribution across deep-water systems and relationship to linked debrites, is important for it to be used effectively as a tool to interpret the geological record.

中文翻译：

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TB or not TB：浊积砂岩中的条带

沉积构造的识别和解释是理解沉积过程的基础。带状砂岩是一种神秘的沉积相，包括交替的富含泥浆（作为基质和/或泥屑）和清洁砂层。流体动力学不同粒度的并置与已建立的清洁砂床形态发展模型相矛盾。在这里，来自三个深水系统的露头、地下岩心和岩石学数据，以及受良好约束的古地理环境，被用来描述沉积结构的范围、床形形态和相组合，并量化带状的泥浆含量。条带可以出现在床层的任何部分（底部、中部或顶部），但它通常覆盖在无结构的基底砂岩或泥屑砾岩层之上，并且被干净的平行层状砂岩和/或波纹交叉层状覆盖。带状形态范围从亚平行到由具有不连续泥岩透镜体的低角度层状体组成的床状体，或由向下游过渡到低幅度床波的陡倾前缘组成的不对称床状体，或具有异质前缘的陡倾波纹状床状体。这种类型的带被解释为一系列床型，通过在含泥过渡塞流下的牵引改造，在上级平面床流态中逐渐形成。内聚力和湍流力的平衡以及流动减速率（聚集率）控制着沉积物的类型。带状砂岩和相连的碎屑很少在同一层中并列在一起，因为它们分别优先分布在近端和远端环境中。了解浊积砂岩中条带的起源、其形成条件、其在深水系统中的分布以及与相关碎屑的关系，对于将其有效地用作解释地质记录的工具非常重要。