Collaborative Research: Uplift or climate change? Determining the primary driver of deep canyon incision in the eastern cordillera, southern Peru

合作研究：抬升还是气候变化？

• 批准号: 1842172
• 负责人: Nadine McQuarrie
• 金额: $ 27.11万
• 依托单位: University of Pittsburgh
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1842172&HistoricalAwards=false
• 关键词: Collaborative; Research; Uplift; climate; change

Competition between the growth of new topography by tectonic uplift and erosion that wears it down occurs in many mountain regions. Earth scientists recognize that the ability of rivers to erode depends on how much water is delivered to the mountains, and that changes between wetter or dryer climates should influence topography. The expectation is that changes in climate and the resulting change in erosion are reflected in the topography of a landscape. This project focuses on the Eastern Cordillera of southern Peru, where deep canyons carved into the Central Andean Plateau margin reflect either tectonic uplift or an increase in erosional efficiency due to climate change. The research incorporates newly-developed methods for diagnosing the effects of climate on topography as part of a field-based investigation to determine the degree to which climate-driven changes in erosional efficiency are responsible for canyon cutting. New remote analysis methods are used to differentiate signatures of tectonic uplift driven erosion and climate driven erosion in topography. Improving the fidelity of these remote methods has considerable societal value because they are an inexpensive and efficient means of hazard assessment in areas where the presence or absence of tectonic uplift, and the resulting effect on seismicity, are uncertain. Additionally, this project wll benefit society by: 1) essential STEM training of three US graduate students including two women, as well as several Peruvian undergraduates; 2) international collaborations with both Peruvian and German universities; and 3) improved STEM education development in Peru and US at the undergraduate, graduate, and professional levels.Determination of an active tectonic driver of mountain uplift and the geometry of related structures is critical to resolving how strongly climate and tectonics are coupled. This project tests competing hypotheses for the proximal drivers of canyon cutting into the Eastern Cordillera: incision driven by active rock uplift vs. incision into a previously uplifted plateau margin triggered by climate change. Integration of observations and analyses of the deformation history, landscape morphology, precipitation patterns, and spatial and temporal patterns of erosion and exhumation is used to definitively and quantitatively evaluate the relative importance of active rock uplift and climate change in landscape evolution. Analyses focus on: 1. estimating millennial-scale erosion rates from cosmogenic 10Be concentrations in modern river sands, 2. assessing the role of rainfall in the relation between topography and erosion rate, 3. analyzing cooling ages of low-temperature thermochronometers (AHe, AFT, ZHe) provided by a complementary study, 4. refining geologic mapping and developing balanced cross sections, and 5. integrating all data in models to quantitatively test hypotheses. Results will have broad implications for: 1. the general applicability and fidelity of proposed methods for diagnosing the primary causes of canyon cutting based on analysis of geomorphic data, 2. further development of a methodology to quantitatively link geometry, displacement and rates on faults to exhumation rates, erosion rate patterns and the resulting landscape morphology, 3. quantitative, observation-based understanding of the sensitivity of erosion rates to annual rainfall, and 4. understanding of the nature and strength of linkages among climate, topography, erosion, and tectonics.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.

在许多山区发生的构造隆起与侵蚀的新地形增长之间的竞争是在许多山区发生的。地球科学家认识到，河流侵蚀的能力取决于向山脉输送多少水，并且潮湿或烘干机气候之间的变化应影响地形。 期望气候变化和侵蚀的导致变化反映在景观的地形中。该项目的重点是秘鲁南部的东部科尔迪利拉，那里的深峡谷雕刻到中部安第斯高原边缘，反映了构造隆起或由于气候变化而导致的侵蚀效率的提高。该研究结合了新开发的方法，用于诊断气候对地形的影响，这是基于现场的研究的一部分，以确定气候驱动的侵蚀效率变化导致峡谷切割负责的程度。新的远程分析方法用于区分地形中构造隆起驱动的侵蚀和气候驱动侵蚀的特征。提高这些远程方法的忠诚度具有相当大的社会价值，因为它们是在存在或不存在构造或不存在构造或不存在对地震性的影响的地区的廉价和有效危险评估手段。此外，该项目将使社会受益：1）三名美国研究生的基本STEM培训，包括两名妇女以及几名秘鲁大学的本科生； 2）与秘鲁和德国大学的国际合作； 3）改善了秘鲁和我们在本科，研究生和专业水平的STEM教育发展。确定山上隆起的积极构造驱动因素和相关结构的几何形状对于解决如何强烈的气候和构造构造的方式至关重要。该项目测试了峡谷近端驱动因素切入东部山脉的近端驱动因素的竞争假设：由主动岩石隆起与切口驱动的切口，进入先前隆升的高原边缘，这是由气候变化触发的。对变形历史，景观形态，降水模式以及侵蚀和挖掘的空间和时间模式的观察和分析的整合用于确定和定量评估景观演化中活动岩石升高和气候变化的相对重要性。分析的重点是：1。估计现代河砂中的千禧一代侵蚀率，2。评估降雨的作用在地形和侵蚀速率之间的关系中，3。分析低温热对象的冷却年龄，由辅助研究和互补的研究和互补的研究和4个。将模型中的所有数据集成以定量检验假设。结果将对以下方式具有广泛的含义：1。基于对地貌数据的分析的分析，提出的方法的一般适用性和忠诚度，用于诊断峡谷切割的主要原因，2。进一步开发一种方法，以定量的几何形状，位移和速率上的位移和速率上的速率与挖掘速率，磨蚀速率和纪念率的速度相关率，以验证速度的速度，并依赖于年度敏感性。降雨和4。对气候，地形，侵蚀和构造之间的联系的性质和力量的理解。该奖项反映了NSF的法定任务，并且使用基金会的知识分子优点和更广泛的影响审查标准，被认为值得通过评估来支持。