Many published interpretations of ancient fluvial systems have relied on observations of extensive outcrops of thick successions. This paper, in contrast, demonstrates that a regional understanding of palaeoriver kinematics, depositional setting and sedimentation rates can be interpreted from local sedimentological measurements of bedform and barform strata. Dune and bar strata, channel planform geometry and bed topography are measured within exhumed fluvial strata exposed as ridges in the Ruby Ranch Member of the Cretaceous Cedar Mountain Formation, Utah, USA. The ridges are composed of lithified stacked channel belts, representing at least five or six reoccupations of a single‐strand channel. Lateral sections reveal well‐preserved barforms constructed of subaqueous dune cross‐sets. The topography of palaeobarforms is preserved along the top surface of the outcrops. Comparisons of the channel‐belt centreline to local palaeotransport directions indicate that channel planform geometry was preserved through the re‐occupations, rather than being obscured by lateral migration. Rapid avulsions preserved the state of the active channel bed and its individual bars at the time of abandonment. Inferred minimum sedimentation durations for the preserved elements, inferred from cross‐set thickness distributions and assumed bedform migration rates, vary within a belt from one to ten days. Using only these local sedimentological measurements, the depositional setting is interpreted as a fluvial megafan, given the similarity in river kinematics. This paper provides a systematic methodology for the future synthesis of vertical and planview data, including the drone‐equipped 2020 Mars Rover mission to exhumed fluvial and deltaic strata.

中文翻译：

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挖掘出的河道带的解剖结构：美国犹他州白垩纪雪松山组红宝石牧场成员的河床到带尺度河流运动学

许多已发表的对古代河流系统的解释都依赖于对厚层序列的广泛露头的观察。相比之下，本文表明，可以通过对底状和棒状地层的局部沉积学测量来解释对古生物运动学、沉积环境和沉积速率的区域理解。在美国犹他州白垩纪雪松山地层的红宝石牧场成员中，在挖掘出的河流地层中测量沙丘和酒吧地层、水道平面几何形状和河床地形。山脊由岩化堆积的河道带组成，代表至少有五到六个单股河道的重新占据。横向剖面显示由水下沙丘交叉组构成的保存完好的棒状体。沿露头的顶面保留了古柱状体的地形。通道带中心线与当地古运输方向的比较表明，通道平面几何形状通过重新占据而得以保留，而不是被横向迁移所掩盖。在废弃时，快速撕脱保留了活跃的河床及其各个酒吧的状态。从交叉集厚度分布和假定的床型迁移率推断出的保存元素的最小沉积持续时间在一个带内从 1 天到 10 天不等。考虑到河流运动学的相似性，仅使用这些局部沉积学测量，沉积环境就被解释为河流巨扇。