Collaborative Research: An integrated mantle to surface study of the causes and consequences of high topography in the Northern US Cordillera

合作研究：对美国北部科迪勒拉山脉高地貌的原因和后果进行地幔到地表的综合研究

基本信息

批准号：
1727046
负责人：
Alison Duvall
金额：
$ 26.89万
依托单位：
University of Washington
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2017
资助国家：
美国
起止时间：
2017-09-01 至 2022-08-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1727046&HistoricalAwards=false
关键词：
Collaborative Research integrated mantle surface

项目摘要

Recent theoretical advances suggest processes occurring deep within Earth's mantle can have significant impacts on topography at Earth's surface. As topographic history of a region can influence the climate and biologic evolution, understanding the role of the mantle in shaping the landscape is paramount to understanding the Earth as a system. A major barrier to the study of mantle and surface process linkages is that few locations exist where time histories of past mantle and surface events can be well constrained. The inland northwest, which includes the well-studied passage of the Yellowstone hotspot, offers a unique opportunity to examine the role mantle dynamics play in mountain uplift and landscape evolution. This project, which focuses on field sites in Oregon and Idaho, is designed as an integrated mantle to surface study that quantifies the regional erosion history and the structure of the upper mantle beneath this region. Results from this work will motivate generalized models incorporating different mantle processes and the topographic response to a range in uplift patterns. As a result, our findings, while specific to our field sites, may help shed light on mantle and surface interactions around the globe. The project will support three graduate students and three Primary Investigators from separate collaborating research institutions. The project also unites academic scientists and research students with public educators and science communicators through a partnership with two eastern Oregon organizations: Wallowa Resources, an organization that engages in educational outreach, environmental action, and renewable energy programs and Wallowology, the only natural history museum in this region.The role of mantle dynamics in driving uplift and landscape evolution is a critical and poorly understood facet of geodynamics and geomorphology research. This project will explore mantle driven epeiorogenic uplift and landscape evolution north of the Yellowstone plume track in the rugged and mountainous Inland Northwest of the United States. Nowhere else has a continent experienced such a recent and profound interaction with a mantle plume, making this area the ideal candidate for the examination of lithosphere-scale responses to mantle dynamics. Guiding our investigation are four testable hypotheses of lithospheric and landscape responses to the Yellowstone plume: (1) uplift and erosion following lithospheric loss through delamination, (2) uplift and erosion following lithospheric loss through drip-like Rayleigh-Taylor convection, (3) uplift and erosion following flattening of the buoyant Yellowstone plume, and (4) erosion driven by faulting induced drainage reorganization. We will build on a strong foundation of prior seismic, geologic and landscape studies across northeastern Oregon and central Idaho. This targeted study will resolve regional landscape evolution and its relation to imaged mantle structure via the integration of geologic and geomorphic field observations, low-temperature thermochronology, and detrital cosmogenic radionuclide derived erosion rates and mantle tomography through geodynamic and landscape evolution modeling. The research will generate models that relate mantle dynamics to uplift and landscape development, constrained by data from our study area and applicable to other locations throughout earth history. This work will help to refine plate-tectonics theory by providing a robust study of intraplate deformation not related to plate boundary forces. Furthermore, we anticipate this study will give the clearest-yet measure of the importance of sub-crustal mantle deformation on landscape evolution, a critical topic in studies from the Andes to Tibet.

最近的理论进步表明，在地球地幔中深处发生的过程可能会对地球表面的地形产生重大影响。由于区域的地形历史可以影响气候和生物学的进化，因此了解地幔在塑造景观中的作用对于理解地球作为系统至关重要。研究地幔和表面过程联系的主要障碍是，很少有在过去的地幔和表面事件的时间历史可以受到限制的位置。西北内陆西北部，其中包括黄石热点的经过深入研究的通道，它提供了一个独特的机会，可以检查地幔动态在山区隆起和景观演化中的作用。该项目的重点是俄勒冈州和爱达荷州的现场地点，被设计为综合地幔，以量化该地区下面的区域侵蚀历史和上层地幔的结构。这项工作的结果将激发包含不同地幔过程的广义模型以及对隆升模式中范围的地形响应。结果，我们的发现虽然特定于我们的现场地点，但可能有助于阐明全球周围的地幔和表面相互作用。该项目将支持来自不同合作研究机构的三名研究生和三名主要研究人员。该项目还通过与两个俄勒冈州东部组织的合作伙伴关系：Wallowa Resources，一个从事教育外展，环境行动以及可再生能源计划和瓦洛学的组织，将学术科学家和研究生与公共教育者和科学沟通者团结在一起，该组织是该地区唯一的自然历史博物馆。在该地区唯一的自然历史博物馆。地幔动态在促进地面和地面的范围和不良的努力和不良的努力和不良的态度和不良的努力和不良的态度。该项目将探索在美国西北部崎and山内陆的黄石羽流轨道以北的地幔驱动的上皮隆起和景观进化。在其他地方，没有一个大陆与地幔羽流相互作用，这使该区域成为检查岩石圈尺度对地幔动力学反应的理想候选者。 Guiding our investigation are four testable hypotheses of lithospheric and landscape responses to the Yellowstone plume: (1) uplift and erosion following lithospheric loss through delamination, (2) uplift and erosion following lithospheric loss through drip-like Rayleigh-Taylor convection, (3) uplift and erosion following flattening of the buoyant Yellowstone plume, and (4) erosion driven by faulting诱导排水重组。我们将建立在俄勒冈州东北部和爱达荷州中部的先前地震，地质和景观研究基础上。这项有针对性的研究将通过整合地质和地质景观观测，低温热量学以及碎屑宇宙核素衍生的侵蚀速率和地幔层析成像，通过地质和地幔层析成像，通过地质和景观模拟，通过地质和碎屑宇宙性的放射性核素衍生的侵蚀速率来解决区域景观的演变及其与成像的地幔结构的关系。该研究将生成将地幔动态与提升和景观开发相关联的模型，该模型受我们的研究区域的数据限制，并适用于整个地球历史上的其他位置。这项工作将通过提供与板边界力无关的板内变形研究来帮助完善板块构件理论。此外，我们预计这项研究将赋予最清楚的量度，即对景观进化的近视地幔变形的重要性，这是从安第斯山脉到西藏的研究中的关键主题。