Deciphering the evolutionary history and depositional processes of meandering rivers

河流是将沉积物从侵蚀高地输送到沉积盆地的运输系统的基本方面。从灌溉和航行到野生动物栖息地和饮用水来源，河流在社会中也发挥着重要作用。河流系统行为的剧烈变化也会对基础设施和人类生活产生重大影响(如洪水)。对未来洪水事件的规模和频率以及河流系统将如何应对环境变化的预测存在相当大的不确定性。对过去洪水的沉积和河流系统的演变历史的调查提供了对这些不确定性的洞察。通过记录现代河流系统中正在进行的过程，我们了解了沉积物是如何沉积的以及在什么条件下沉积，并定义了在沉积记录中识别相关沉积物的标准。拟议的研究计划旨在通过研究现代河流的过程及其在化石记录中产生的沉积物，更好地了解河流对内部(例如洪水)和外部(例如气候)强迫的反应。*马尼托巴省西南部的表层沉积物覆盖记录了该地区大约20,000年前开始的冰川消融历史。这包括将阿西尼博因三角洲沉积到曾经覆盖该省大部分地区的冰川湖阿加西湖。随着湖水排干，河流切入三角洲沉积形成了现代的阿西尼博因河流域。正是在这些河流沉积物中，记录了过去的洪水、湖水位的变化和气候条件的变化。拟议的研究计划将调查这些沉积物，以洞察洪水事件的规模和频率，以及更广泛地说，河流如何应对不断变化的地球条件。为了扩大观察窗口，还将检查在艾伯塔省东南部荒地暴露出来的河流沉积物化石。古代河流沉积是地球条件变化的未被充分利用的记录，它们代表了比人类观察更长的档案(&gt；104年)。这一综合分析将提供对河流过程和沉积产物的全面了解，从而为预测未来的洪水事件和河流对不断变化的气候的反应提供信息。拟议的研究计划将培训14名HQP，并产生直接适用于洪灾缓解工作以及河流沉积中包含的石油和天然气资源开发的结果。

Rivers are essential aspects of transport systems that deliver sediment from erosional highlands to depositional basins. Rivers also play a significant role in society, from irrigation and navigation, to wildlife habitat and sources of drinking water. Drastic changes in river system behavior can also significantly impact infrastructure and human lives (e.g., floods). There is considerable uncertainty in predictions of the magnitude and frequency of future flood events and how river systems will respond to environmental change. Investigation into the deposits of past floods and the evolutionary history of river systems provides insight into these uncertainties. By documenting ongoing processes in modern river systems, we learn how and under what conditions sediment is deposited, and define criteria for recognition of associated sediments in the depositional record. The proposed research program aims to better understand how rivers respond to internal (e.g., floods) and external (e.g., climate) forcing by studying the processes of modern rivers, and their resulting deposits in the fossilized record.***The surficial sediment cover of southwestern Manitoba records the de-glaciation history of the area, beginning around 20,000 years ago. This includes the deposition of the Assiniboine Delta into glacial Lake Agassiz, which once covered much of the province. As the lake drained, fluvial incision into the deltaic deposits created the modern Assiniboine River valley. It is within these river deposits that an archive of past floods, changing lake levels, and varying climatic conditions is recorded. The proposed research program will investigate these deposits to yield insight into the magnitude and frequency of flood events, and more generally, how rivers respond to changing Earth conditions. To expand the window of observation, fossilized river deposits exposed in the “badlands” of southeastern Alberta will also be examined. Ancient fluvial deposits are an underutilized record of changing Earth conditions, and they represent a much longer archive (>104 yrs) than human observation. This integrated analysis will provide a holistic understanding of river processes and sedimentary products, which will inform predictions of future flood events and river response to a changing climate. The proposed research program will train 14 HQPs and produce results that are directly applicable to flood mitigation efforts, as well as the development of oil and gas resources contained in fluvial deposits.