EAR-PF: A Deep Critical Zone Observatory: Towards understanding the relationships of denudation and weathering through time and space

EAR-PF：深层关键带观测站：了解时空剥蚀和风化之间的关系

• 批准号: 2052835
• 负责人: Brendon Quirk
• 金额: $ 17.4万
• 依托单位: Quirk, Brendon James
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-01 至 2022-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2052835&HistoricalAwards=false
• 关键词: EAR; PF; Deep; Critical; Zone

Dr. Brendon Quirk has been awarded an NSF EAR Postdoctoral Fellowship to study the relationship of global climate conditions and the breakdown of rocks using lake sediments. The work will be conducted at Purdue University under the mentorship of Dr. Darryl Granger. Understanding how rocks break down (weather) and how the resulting material is transported (erosion) throughout geologic history is critical for understanding how Earth’s climate has evolved. Specifically, the breakdown of rock through chemical reactions may help to stabilize global climate and produce a habitable Earth. This work will use lake sediments to understand how different climate conditions affect rates of weathering and erosion of rock and soil across Earth’s surface. The anticipated results will be useful for evaluating specific models of weathering and erosion in geologic history and may shed light on potential natural feedbacks between erosion, weathering, and climate. The project includes outreach and mentoring programs for first-generation college students to conduct research. The development of accessible laboratory techniques designed to reduce barriers to conducting research into global climate is another activity supported by this research. Understanding variations in denudation (the sum of physical and chemical weathering fluxes) of Earth’s surface through time and space remains one of most pressing problems in the earth sciences. Chemical weathering of silicate minerals is thought to be one of the main processes which regulate the global carbon cycle. Thus, denudation may act to stabilize global climate over geologic timescales and may be an important factor in earth’s habitability. However, high-resolution records of terrestrial denudation and weathering for the Quaternary period are rare and questions remain if and how erosion and weathering might interact to regulate and stabilize the chemical weathering flux across interglacial-glacial timescales. The work proposed here seeks to address these outstanding questions by quantifying paleo-denudation and weathering rates spanning several glacial-interglacial cycles. This project will use well established methods to quantify paleo-denudation (in situ cosmogenic Be-10) and weathering intensities (chemical depletion fractions) in lacustrine sediment archives as well as calibrate promising new methods (Be-10(meteoric)/Be-9) to quantify each from fine grained, quartz-poor, lake sediments.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.

Brendon Quirk博士被授予NSF博士后奖学金，研究全球气候条件与使用湖泊沉积物分解岩石的关系。这项工作将在达里尔格兰杰博士的指导下在普渡大学进行。了解岩石如何分解（天气）以及由此产生的物质如何在整个地质历史中运输（侵蚀）对于了解地球气候如何演变至关重要。具体而言，通过化学反应分解岩石可能有助于稳定全球气候并产生可居住的地球。这项工作将利用湖泊沉积物来了解不同的气候条件如何影响地球表面岩石和土壤的风化和侵蚀速率。预期的结果将有助于评估地质历史中的风化和侵蚀的特定模型，并可能揭示侵蚀，风化和气候之间的潜在自然反馈。该项目包括为第一代大学生开展研究的推广和指导计划。 这项研究支持的另一项活动是开发便于使用的实验室技术，以减少对全球气候进行研究的障碍。 了解地球表面剥蚀（物理和化学风化通量的总和）在时间和空间上的变化仍然是地球科学中最紧迫的问题之一。硅酸盐矿物的化学风化被认为是调节全球碳循环的主要过程之一。因此，剥蚀作用可能在地质时间尺度上起到稳定全球气候的作用，并且可能是地球可居住性的一个重要因素。然而，高分辨率记录的第四纪陆地剥蚀和风化作用是罕见的，问题仍然存在，如果以及如何侵蚀和风化作用可能相互作用，以调节和稳定的化学风化通量跨越间冰期-冰期的时间尺度。这里提出的工作旨在解决这些悬而未决的问题，通过量化古剥蚀和风化率跨越几个冰川间冰期周期。本项目将使用完善的方法来量化古剥蚀（原位宇宙成因Be-10）和风化强度（化学消耗分数）在湖泊沉积物档案，以及校准有前途的新方法（Be-10（流星体）/Be-9）来量化每一种来自细粒、贫石英、该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。