Collaborative Research: The Origin of Natural Levees

9811860 slingerland本研究将考察冲积洪泛区天然堤坝的起源、演化、形态和沉积学特征，重点研究不列颠哥伦比亚省戈尔登附近的哥伦比亚河上游和萨斯喀彻温省东部坎伯兰沼泽的萨斯喀彻温河。尽管堤坝通常被描述为相对简单的特征，但它们相当复杂，显示出各种各样的大小、形状、坡度和纹理属性，这些属性可能反映了河道和洪泛平原配置、河道历史、泥沙负荷、洪水特征和洪水历史的控制。这三部分的调查将包括(1)堤防形态参数的测量和分析，(2)现代堤防形成的水力测量和数学建模，以及(3)堤防沉积物的沉积学调查，重点研究从堤防沉积物中可以推断出的河道历史和堤防演化模式。预计该项目的结果将：(i)允许对拟议的概念模型进行测试，该模型是指在河漫滩崩裂后，天然堤坝的发展和增长与河道的演变同时进行的；（ii）更清楚地认识到在堤坝发展的不同阶段，河道到河漫滩的沉积物转移的扩散和调节机制的相对重要性；(3)有助于更好地了解堤防沉积物及其在冲积沉积层序中的相对重要性。

9811860SlingerlandThis study will examine the origin, evolution morphological and sedimentological characteristics of natural levees in alluvial floodplains, concentrating on the upper Columbia River near Golden, British Columbia, and the Saskatchewan River at the Cumberland Marshes, eastern Saskatchewan. Despite common depictions of levees as being relatively simple features, they are quite complex, displaying a wide range of sizes, shapes, slopes, and textural attributes that likely reflect controls of channel and floodplain configurations, channel history, sediment load, flood character and flood history. This three-part investigation will include (1) measurement and analysis of morphometric parameters of levees, (2) hydraulic field measurements and mathematical modeling of modern levee formation, and (3) sedimentological investigations of levee deposits, focusing on the question of what can be inferred about channel history and evolutionary patterns of levees from their deposits. The results of this project are expected to (i) permit testing of a proposed conceptual model for the development and growth of natural levees concurrently with the evolution of channels following avulsion in river floodplains, (ii) provide a clearer sense of the relative importance of diffusive and adjective mechanisms of channel-to-floodplain sediment transfer during different stages of levee development, and (iii) result in a better understanding of levee deposits and their relative importance in successions of alluvial sediments.