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，并设定了景观对气候和构造变化响应的速度。但是，我们目前缺乏瀑布侵蚀的机械模型，这抑制了我们预测景观对环境扰动反应的能力。该项目的目的是通过在室内瀑布实验室中的实验和监测自然界的瀑布过程的结合来填补这一知识差距。 瀑布实验将在加利福尼亚理工学院的新最先进的液压和沉积物水槽中完成。 这项工作将导致用于沉积物运输能力和瀑布暴跌池侵蚀的数学理论。 从水槽实验开发的模型将针对加利福尼亚州圣加布里埃尔山脉的活跃瀑布收集的沉积物传输数据进行测试，并在较长的时间表上与以前研究收集的新的瀑布撤退率数据库。除了得出瀑布撤退的衍生和测试模型外，我们的工作还将有助于理解山流中的沉积物路由和储存，因为瀑布池池是天然的临时沉积物水槽，对于减轻河流洪水危害和了解依赖夏季池的水生生物的栖息地而言重要性。 该提案的重点是一项综合研究和教育计划。瀑布在自然景观中无处不在且令人敬畏的地形。他们提供了一种很好的媒介，使学生和公众在侵蚀和沉积问题以及景观进化中感兴趣。 拟议的教育计划包括指导夏季本科研究研究员和将直接参与研究的博士生。 通过加州理工学院的夏季本科研究奖学金计划，本科生将定义和制定一个项目，编写研究建议，执行实验室和实地考试的子集，提交技术论文，并在专业技术会议上建立的研讨会上进行口头介绍。 外展活动将集中于帕萨迪纳统一学区（P.U.S.D.）的学生和老师的旅行，课堂探访和野外游览，该地区大多数学生来自地球科学中代表性不足的小组。