Abstract The formative mechanisms of linear (longitudinal) dunes and dunefields remain uncertain, and multiple hypotheses have been proposed. A central debate is the degree to which dunes act as along-dune sediment transport corridors, implying that dunes grow primarily by extension, or whether they are comprised of locally-derived sands moved from adjacent interdunes (the ‘wind-rift’ model). Sediment fingerprinting studies, with origins in fluvial science, have been shown to offer the possibility to trace the provenance of aeolian sands, and thus elucidate transport pathways. Two models (a Monte Carlo framework and a Generalized Likelihood Uncertainty Estimate framework) are used here to provide quantitative estimates of the sediment sources that have supplied a linear dune in the central Simpson Desert of central Australia. Four possible sources are identified that may have supplied the dune; two adjacent interdunes, one upwind low ridge of sand, and a merging upwind dune. Two sites near the dune's crest are used as the target and provided twenty surface samples for analysis. Following geochemical assay, stepwise discriminant function analysis identified optimum elemental sediment fingerprints for a variety of possible sediment pathway configurations. Results suggest that the sands of the dune are sourced predominantly from upwind dunes and sand sources, and that likely contributions from neighbouring dune swales are typically The findings suggest recent sediment accretion of a linear dune dominated by along-dune sand flux, and thus support an extensional component for the development of such dunes. Whilst it is noted that at a point-by-point basis this might not exclude accretion by vertical growth, as some have observed, there is no clear support for a substantive contribution to the dune sands from adjacent interdunes. Moreover, the use of contemporary sediment fingerprinting methods to question hypotheses of aeolian geomorphology suggests that such methods have great potential for addressing other terrestrial geomorphological questions where identifying sediment pathways can provide vital insight.

中文翻译：

---

基于复合沉积物指纹的物源分析测试线性沙丘形成模型

摘要 线性（纵向）沙丘和沙丘场的形成机制尚不确定，并提出了多种假设。一个核心争论是沙丘作为沿沙丘沉积物运输走廊的程度，这意味着沙丘主要通过延伸生长，或者它们是否由从相邻沙丘间移动的当地沙子组成（“风-裂谷”模型）。起源于河流科学的沉积物指纹研究已被证明可以提供追踪风积沙来源的可能性，从而阐明运输途径。这里使用了两个模型（蒙特卡罗框架和广义似然不确定性估计框架）来提供对澳大利亚中部辛普森沙漠中部提供线性沙丘的沉积物来源的定量估计。确定了可能提供沙丘的四个可能来源；两个相邻的沙丘，一个上风低沙脊和一个合并的上风沙丘。沙丘顶部附近的两个地点被用作目标，并提供了二十个表面样本进行分析。在地球化学分析之后，逐步判别函数分析确定了各种可能的沉积路径配置的最佳元素沉积指纹。结果表明，沙丘的沙子主要来自逆风沙丘和沙源，相邻沙丘洼地的可能贡献通常是这种沙丘的发展的延伸部分。虽然有人指出，在逐点基础上，这可能不排除垂直增长的吸积，正如一些人所观察到的那样，没有明确支持相邻沙丘对沙丘砂的实质性贡献。此外，使用当代沉积物指纹识别方法来质疑风成地貌学的假设表明，这些方法在解决其他陆地地貌学问题方面具有巨大潜力，在这些问题中，识别沉积物路径可以提供重要的洞察力。