CAREER: Resolving the detrital thermal signatures and natural biases of sediment recycling and weathering in orogenic systems

职业：解决造山系统中沉积物回收和风化的碎屑热特征和自然偏差

• 批准号: 2045695
• 负责人: Julie Fosdick
• 金额: $ 58.79万
• 依托单位: University of Connecticut
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-01 至 2026-06-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2045695&HistoricalAwards=false
• 关键词: CAREER; Resolving; detrital; thermal; signatures

The weathering and erosion of the continents is a central component of the rock cycle and modification of the Earth’s surface. Yet, a fundamental problem in Earth sciences is the intrinsic difficulty in recognizing sediment derived from the erosion of primary crystalline rocks versus sediment that may represent multiple episodes of weathering, erosion, and transport. Resolving these differences is essential to understanding the growth of the continental crust, continental-scale river drainage reversals, and glacial-interglacial landscape change. This project will focus on the signals of recycling on the geochemistry of detrital minerals during the evolution of the Sierras Pampeanas province of South America. The Sierras Pampeanas are the modern archetype for the lithospheric response to flat slab subduction and an ideal setting to develop improved metrics for geochemical signatures of recycling needed to better understand the evolution of the continental lithosphere. Educational activities focus on increasing participation and retention of under-represented groups in STEM (science, technology, engineering and mathematics) by bridging high school through graduate school laboratory and field experiences. Partnership with the University College Access Program at the University of Connecticut will develop summer internships designed for high school students to gain early exposure to Earth sciences. Geologic field trips in the Hartford Rift Basin, hands-on and virtual laboratory experiments in thermochronology, and mentoring by undergraduate and graduate students will broaden student interns’ experiences and success in higher education STEM opportunities. Graduate student training in thermochronology will contribute towards a stronger technical workforce in support of major instrumentation and technological initiatives in the Earth sciences. Project collaborations will enhance research infrastructure and education technology transfer among collaborating U.S. and Argentine institutions.This project centers on advancing scientific knowledge of the controlling factors and diagnostic geochemical signatures of sediment recycling during the evolution of the continental lithosphere. By using the emerging detrital monazite thermochronometer alongside established zircon geochronology, thermochronology, and sedimentary compositional archives, an integrated sedimentary provenance analysis will capture the discrete polycyclic histories of continental growth and basin evolution in the Sierras Pampeanas. Research components of the program include: (1) fieldwork and sample collection, (2) detrital zircon geochronology and thermochronometry, (3) development of detrital monazite double-dating thorium-lead-helium (Th-Pb-He) thermochronometry, (4) compositional provenance analysis, and (5) synthesis and thermal history modeling of datasets to explore how different sediment recycling scenarios impact detrital datasets. This research will generate detrital fingerprinting and source characterization of the Sierras Pampeanas to track the influence of pre-existing structures and basin inversion on sediment transfer during flat-slab deformation; streamlined analytical workflows for detrital monazite geochronology, geochemistry, and thermochronometry; and development of a new multiproxy metric for sediment recycling in polycyclic settings. These fundamental advances have wide-ranging applicability in the Earth sciences for correctly quantifying continental weathering and erosion rates, crustal growth, source-to-sink sediment budgets, and constraining rock deformational histories tied to tectonic and earthquake cycles.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.

大陆的风化和侵蚀是岩石循环和地球表面改变的核心组成部分，然而，地球科学的一个基本问题是识别源自原生结晶岩石侵蚀的沉积物与可能代表的沉积物之间的内在困难。解决这些差异对于了解大陆地壳的生长、大陆规模的河流排水逆转和冰川间冰期景观变化至关重要。南美洲潘皮纳斯山脉省演化过程中碎屑矿物的地球化学 潘皮纳斯山脉是岩石圈对平板俯冲响应的现代原型，也是开发更好地了解演化所需的回收地球化学特征的改进指标的理想环境。教育活动的重点是通过研究生院实验室和高中之间的桥梁，提高代表性不足的群体对 STEM（科学、技术、工程和数学）的参与和保留。与康涅狄格大学大学学院合作项目合作，将为高中生提供暑期实习机会，让他们尽早接触哈特福德裂谷盆地的地质实地考察、热年代学的实践和虚拟实验室实验。本科生和研究生的指导将扩大学生实习生的经验和在高等教育 STEM 方面取得成功的机会。热年代学方面的研究生培训将有助于培养更强大的技术队伍，以支持地球科学领域的主要仪器和技术举措。提高美国和阿根廷合作机构之间的研究基础设施和教育技术转让。该项目的重点是通过使用新兴的碎屑独居石测温仪以及已建立的锆石地质年代学，推进大陆岩石圈演化过程中沉积物循环的控制因素和诊断地球化学特征的科学知识。 、热年代学和沉积成分档案，综合沉积物源分析将捕捉潘皮纳斯山脉研究中大陆生长和盆地演化的离散多旋历史。该方案的组成部分包括：(1) 实地考察和样品采集，(2) 碎屑锆石地质年代学和热测时法，(3) 开发碎屑独居石双重测年钍铅氦（Th-Pb-He）热测年法，(4)成分来源分析，以及（5）数据集的合成和热历史建模，以探索不同的沉积物循环情景如何影响碎屑数据集。这项研究将生成碎屑指纹。潘皮纳斯山脉的源头表征，以跟踪现有构造和盆地反演对平板变形过程中沉积物转移的影响；简化碎屑独居石地质年代学、地球化学和热年代学分析工作流程，并开发新的沉积物多代理度量；这些基本进展在地球科学中具有广泛的适用性，可以正确量化大陆风化和侵蚀率、地壳生长、该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。