NSFGEO-NERC Collaborative Research: Coupling Erosion, Weathering, and Hydrologic Function in an Active Orogenic System

NSFGEO-NERC 合作研究：活跃造山系统中侵蚀、风化和水文功能的耦合

• 批准号: 2021299
• 负责人: Dimitrios Zekkos
• 金额: $ 45.12万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-15 至 2024-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2021299&HistoricalAwards=false
• 关键词: NSFGEO; NERC; Collaborative; Research; Coupling

Mountain ranges are some of the most spectacular features of the Earth’s surface, but their importance extends far beyond their photogenic nature. Mountains play critical roles in sustaining key natural resources, such as supplying fresh water to large human populations. Mountainous regions are the site of many destructive natural hazards, such as landslides and floods. In addition, mountains are where fresh rocks are exposed to water and the atmosphere, resulting in chemical reactions that can modify carbon dioxide and climate over geologic time. These processes are all closely interconnected, yet they have been largely studied in isolation. This project will examine the physical and chemical transformation of rock together with the flow of water and Earth materials within the scope of one integrated research endeavor. The project will examine these processes in a valley in the Himalaya Mountains of Nepal where topography changes from more subdued in the south to high mountains in the north. Cutting-edge techniques for documenting the nature and rate of landscape change will be applied to determine the role of mountains in the Earth system. Models that illustrate how all these processes interact and the effects they produce will be developed to forecast future changes and apply the results to other regions. The research will involve training of multiple graduate and undergraduate researchers and will involve collaboration among researchers from four countries. The collisional boundaries between Earth’s tectonic plates produce dramatic mountain ranges that generate destructive natural hazards as well as chemical and physical exchanges that control the surface environment. This project will comprise a multi-disciplinary investigation of four interrelated problems: (1) how rock is transformed physically and chemically during exhumation in tectonically-active mountains; (2) how the steep mountainous topography of active orogens develops, and particularly what the role is for landslides; (3) how water makes its way from precipitation, through the subsurface, and into streams and rivers draining active orogens; and (4) how chemical weathering depends on tectonic and climatic conditions in these settings. The project will investigate the Melamchi Khola valley in central Nepal, where a pronounced south-to-north gradient in exhumation rate offers an ideal opportunity to document system-level relationships among tectonics, topographic evolution, erosion, hydrology, and chemical weathering in an archetypal setting of collisional tectonics. The research will (1) characterize rock mass across scales from the micron to kilometer, including via geophysical imaging, borehole drilling, and rock testing; (2) quantify water transit times and chemical weathering reactions and fluxes, via groundwater dating, stream and spring monitoring, and reactive transport modeling; and (3) develop models of landscape evolution that account for the interconnected processes that regulate landslides, which are the primary vehicles for hillslope erosion in these settings. The project includes diverse opportunities for student education, development of international collaboration. A summer school for early-career researchers will expand the educational reach, and a short course on active source seismology will be held in Kathmandu to broaden the training opportunities for Nepali scientists.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

山脉是地球表面最壮观的特征，但它们的重要性远远超出了其上镜的性质。山区在维持关键自然资源中起着关键作用，例如向大量人口供应淡水。山区是许多破坏性自然灾害的所在地，例如滑坡和地板。此外，山是新鲜岩石暴露于水和大气的地方，导致化学反应可以在地质时期改变二氧化碳和气候。这些过程都是紧密相互联系的，但是它们在很大程度上是孤立的。该项目将检查岩石的物理和化学转化，以及一项综合研究努力范围内的水和地球材料的流动。该项目将在尼泊尔喜马拉雅山脉的一个山谷中检查这些过程，那里的地形从南部的柔和变为北部的高山。记录景观变化的性质和速率的尖端技术将应用于确定山区在地球系统中的作用。说明所有这些过程如何相互作用及其产生的效果的模型将被开发以预测未来的变化并将结果应用于其他地区。该研究将涉及多个研究生和本科研究人员的培训，并将涉及四个国家的研究人员之间的合作。地球构造板之间的碰撞边界产生了巨大的山脉，产生了破坏性的自然危害以及控制地表环境的化学和物理交流。该项目将构成对四个相互关联的问题的多学科研究：（1）在构造活动山脉挖掘过程中，岩石如何进行物理和化学转化； （2）活跃的Orogens开发的蒸汽山地形如何，尤其是滑坡的角色； （3）水如何从降水，地下以及流入河流的河流中流动的河流； （4）化学风化如何取决于这些环境中的构造和杂交条件。该项目将调查尼泊尔中部中部的Melamchi Khola山谷，在该项目中，一个明显的挖掘率向南到北梯度为记录构造，地形演化，侵蚀，水文学和化学风化之间的系统级关系提供了理想的机会。该研究将（1）表征从微米到公里范围的岩石质量，包括通过地球物理成像，钻孔钻孔和岩石测试； （2）通过地下水，溪流和春季监测以及反应性运输模型来量化水交通时间和化学风化反应和通量； （3）开发景观演化模型，以说明调节滑坡的相互联系的过程，这是这些环境中山坡侵蚀的主要工具。该项目包括潜水员的学生教育机会，国际合作的发展。一所早期职业研究人员的暑期学校将扩大教育范围，并将在加德满都举行有关主动来源地震学的简短课程，以扩大尼泊尔科学家的培训机会。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的智力和更广泛影响的评估来通过评估来支持的，这是值得的。