Developing Mechanistic Models for Bedrock Erosion at Waterfalls.

开发瀑布基岩侵蚀的机制模型。

• 批准号: 1147381
• 负责人: Michael Lamb
• 金额: $ 27.5万
• 依托单位: California Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-03-15 至 2016-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1147381&HistoricalAwards=false
• 关键词: Developing; Mechanistic; Models; Bedrock; Erosion

The upstream movement of waterfalls controls the shape of many landscapes and sets the rate by which landscapes respond to changes in climate and tectonics. However, we currently lack mechanistic models for waterfall erosion which inhibits our ability to predict landscape response to environmental perturbations. The goal of this project is to fill this knowledge gap through a combination of experiments in an indoor waterfall laboratory and monitoring waterfall processes in nature. The waterfall experiments will be completed in a new state-of-the-art hydraulic and sediment flume at the California Institute of Technology. This work will lead to mathematical theories for the sediment transport capacity and erosion of waterfall plunge pools. The models developed from flume experiments will be tested against sediment transport data that we will collect at an active waterfall in the San Gabriel Mountains, CA, and over longer timescales against a new database of waterfall retreat rates compiled from previous studies. In addition to deriving and testing models for waterfall retreat, our work will aid understanding sediment routing and storage in mountain streams because waterfall plunge pools are natural temporary sediment sinks, with importance for mitigating river flood hazards and understanding habitats of aquatic organisms that depend on pools in summer months. A focus of this proposal is an integrated research and education program. Waterfalls are ubiquitous and awe-inspiring landforms in the natural landscape; they provide a great medium through which to interest students and the public in issues of erosion and sedimentation, as well as landscape evolution. The proposed educational program includes mentoring summer undergraduate research fellows and PhD students who will be directly involved with the research. Through the Caltech Summer Undergraduate Research Fellowship program, undergraduate students will define and develop a project, write research proposals, carry out subsets of the laboratory and field work, submit a technical paper, and give an oral presentation at a symposium modeled on a professional technical meeting. Outreach events will be focused on tours, classroom visits, and field excursions for students and teachers in the Pasadena Unified School District (P.U.S.D.), a district where the majority of students are from groups under-represented in geosciences.

瀑布的上游运动控制着许多景观的形状，并决定了景观对气候和构造变化的反应速度。然而，我们目前缺乏瀑布侵蚀的机制模型，这限制了我们预测景观对环境扰动的响应的能力。该项目的目标是通过室内瀑布实验室的实验和监测自然界中的瀑布过程相结合来填补这一知识空白。 瀑布实验将在加州理工学院的一个新的最先进的水力和沉积水槽中完成。 这项工作将产生有关瀑布水池的泥沙输送能力和侵蚀的数学理论。 根据水槽实验开发的模型将根据我们在加利福尼亚州圣盖博山的一个活跃瀑布收集的沉积物传输数据进行测试，并在更长的时间尺度上根据以前的研究编制的瀑布退缩率的新数据库进行测试。除了推导和测试瀑布退缩模型外，我们的工作还将有助于了解山间溪流中的沉积物路径和存储，因为瀑布瀑布池是天然的临时沉积物汇，对于减轻河流洪水灾害和了解依赖于水池的水生生物的栖息地具有重要意义在夏季。 该提案的重点是综合研究和教育计划。瀑布是自然景观中随处可见、令人惊叹的地貌；它们提供了一个很好的媒介，让学生和公众对侵蚀和沉积以及景观演变问题产生兴趣。 拟议的教育计划包括指导将直接参与研究的暑期本科生研究员和博士生。 通过加州理工学院暑期本科生研究奖学金计划，本科生将定义和开发一个项目，撰写研究提案，进行实验室和现场工作的子集，提交技术论文，并在以专业技术为模型的研讨会上进行口头报告。会议。 外展活动的重点是帕萨迪纳联合学区 (P.U.S.D.) 学生和教师的参观、课堂参观和实地考察，该学区的大多数学生来自地球科学领域代表性不足的群体。