Extreme floods are underrepresented in instrumented flow records. Consequently, flood frequency model estimates of extreme floods contain large uncertainty. The lower Tennessee River (LTR) Basin is located within the southeastern United States and is a large, regulated, and socio-economically significant North American river. The flood-of-record for the LTR occurred in 1867 CE. The 1867 flood-of-record is a design flow for the dams built and managed by the Tennessee Valley Authority. Here we develop and apply an extreme paleoflood chronology and use it to improve flood frequency model estimates of large, rare floods. We created an extreme paleoflood chronology that contained paleodischarge estimates for six extreme paleofloods, dating back to 5900 years before present, for a ∼2 km segment of the LTR. We obtained paleoflood hydrologic data from two sources. These included field sampling and analysis of slackwater deposits found in a rock shelter located on a limestone bluff and published extreme paleoflood data from a terrace located within the study segment.

中文翻译：

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全新世热最大古洪水改善了田纳西河流域下游的洪水频率分析（美国）

仪表流量记录中极端洪水的代表性不足。因此，极端洪水的洪水频率模型估计包含很大的不确定性。田纳西河下游 (LTR) 流域位于美国东南部，是一条大型、受监管且具有重要社会经济意义的北美河流。 LTR 的洪水泛滥发生在公元 1867 年。 1867 年创纪录的洪水是田纳西河谷管理局建造和管理的水坝的设计流程。在这里，我们开发并应用了极端古洪水年代学，并用它来改进大规模、罕见洪水的洪水频率模型估计。我们创建了极端古洪水年表，其中包含对 LTR 约 2 公里段的 6 次极端古洪水的古排放估计，可追溯到距今 5900 年前。我们从两个来源获得了古洪水水文数据。其中包括对石灰岩悬崖上的岩石掩体中发现的滞水沉积物进行现场采样和分析，并发布来自研究段内台地的极端古洪水数据。