Abstract Sediment waves, a term that describes the fluvial transport of a discrete sediment influx, have been studied in regard to channel response to infrequent catastrophic events, such as mass movements or dam removal. However, few researchers have studied (1) the potential presence of sediment waves of annual or sub-annual scale in mixed eolian-fluvial geomorphic environments or (2) the role of large wood in sediment wave dispersal. This study addresses both topics through observations of North Sand Creek and East Sand Creek, which flow alongside the active sand dunes of North Sand Hills and East Sand Hills, respectively, in North Park, Colorado. The creeks experience similar seasonal, asynchronous cycles of eolian influx and fluvial transport, although North Sand Creek receives a greater volume of eolian sand. We use repeat photography and repeat measurement of ephemeral terraces to determine whether each creek experiences a sediment wave, and we use repeat measurement of logjam sand wedge volume to examine changes in sand storage associated with logjams over time. Results indicate that North Sand Creek experiences a highly translative sediment wave that is attenuated by logjams. East Sand Creek, on the other hand, does not experience a sediment wave.

中文翻译：

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美国科罗拉多州北部公园的风成-河流环境中年沉积波的阻塞衰减

摘要 泥沙波是描述离散泥沙流入的河流输送的术语，研究了河道对不常见的灾难性事件（例如大规模运动或大坝拆除）的响应。然而，很少有研究人员研究 (1) 在混合风积-河流地貌环境中可能存在年度或次年度规模的沉积波或 (2) 大木材在沉积波扩散中的作用。本研究通过对北沙溪和东沙溪的观察来解决这两个主题，它们分别沿着科罗拉多州北帕克的北沙丘和东沙丘的活跃沙丘流动。这些小溪经历了类似的季节性、不同步的风沙流入和河流运输循环，尽管北沙溪接收了更多的风沙。我们使用重复摄影和对短暂阶地的重复测量来确定每条小溪是否经历了沉积波，并且我们使用对阻塞沙楔体积的重复测量来检查与阻塞相关的沙子存储随时间的变化。结果表明，北沙溪经历了一个高度平移的沉积波，该波被僵局削弱了。另一方面，东沙溪没有经历沉积波。