Discharge event frequency, magnitude and duration all control river channel morphology and sedimentary architecture. Uncertainty persists as to whether alluvial deposits in the rock record are a time-averaged amalgam from all discharge events, or a biased record of larger events. This paper investigates the controls on channel deposit character and subsurface stratigraphic architecture in a river with seasonal discharge and very high inter-annual variability, the Burdekin River of north-east Australia. In such rivers, most sediment movement is restricted to a few days each year and at other times little sediment moves. However, the maximum discharge magnitude does not directly correlate with the amount of morphological change and some big events do not produce large deposits. The Burdekin channel deposits consist of five main depositional elements: (i) unit bars; (ii) vegetation-generated bars; (iii) gravel sheets and lags; (iv) antidune trains; and (v) sand sheets. The proportions of each depositional element preserved in the deposits depend on the history of successive large discharge events, their duration and the rate at which they wane. Events with similar peak magnitude but different rate of decline preserve different event deposits. The high intra-annual and inter-annual discharge variability and rapid rate of stage change make it likely that small to moderate-scale bed morphology will be in disequilibrium with flow conditions most of the time. Consequently, dune and unit bar size and cross-bed set thickness are not good indicators of event or channel size. Antidunes may be more useful as indicators of flow conditions at the time they formed. Rivers with very high coefficient of variance of maximum discharge, such as the Burdekin, form distinctive channel sediment bodies. However, the component parts are such that, if they are examined in isolation, they could lead to misleading interpretation of the nature of the depositional environment if conventional interpretations are used.

中文翻译：

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对高度可变河流的河道沉积的控制：比较澳大利亚伯德金河的水文和事件沉积

排放事件的频率、大小和持续时间都控制着河道形态和沉积结构。关于岩石记录中的冲积沉积物是来自所有排放事件的时间平均汞齐，还是较大事件的有偏差记录，不确定性仍然存在。本文研究了对季节性流量和年际变化非常高的河流（澳大利亚东北部的伯德金河）中河道沉积特征和地下地层结构的控制。在这样的河流中，大部分泥沙运动仅限于每年几天，其他时间几乎没有泥沙运动。然而，最大流量大小与形态变化量没有直接关系，一些大事件不会产生大的沉积物。Burdekin 河道沉积物由五种主要沉积元素组成：(i) 单位酒吧；(ii) 植被生成的酒吧；(iii) 砾石板和石板；(iv) 抗沙丘列车；(v) 砂纸。沉积物中保存的每种沉积元素的比例取决于连续大放电事件的历史、它们的持续时间和它们减弱的速度。具有相似峰值幅度但不同下降率的事件保存不同的事件沉积。年内和年际的高流量变化和快速的阶段变化使得中小规模的床形态可能在大多数时间与流动条件不平衡。因此，沙丘和单元条尺寸以及交叉床层厚度不是事件或通道尺寸的良好指标。反沙丘作为形成时流动状况的指标可能更有用。最大流量变异系数非常高的河流，如 Burdekin，形成独特的河道沉积体。然而，组成部分是这样的，如果单独检查它们，如果使用传统解释，它们可能导致对沉积环境性质的误导性解释。