EAR-PF: An Experimental Investigation of the Rheological Behavior and Seismic Anisotropy Signature of Deep Crustal Amphibole-Rich Rocks

EAR-PF：深地壳富含角闪石岩石的流变行为和地震各向异性特征的实验研究

• 批准号: 1725633
• 负责人: Cailey Condit
• 金额: $ 8.7万
• 依托单位: Condit Cailey B
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-01 至 2021-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1725633&HistoricalAwards=false
• 关键词: EAR; PF; Experimental; Investigation; Rheological

Dr. Cailey Condit has been granted an NSF EAR postdoctoral fellowship to carry out research and educational plans at the Massachusetts Institute of Technology. She will investigate the way amphibole, a common but poorly understood mineral within the earth's crust, behaves when it is deformed under high temperatures and pressures. This work will directly augment our understating of continuous deformation within ductile shear zones in the deep crust, where rocks flow rather than break, and within subduction zones, where oceanic crust is descending beneath continents. This experimental work is aimed at constraining the strength of these highly deformed, amphibole-rich zones and investigating their geophysical properties so that geophysicists can make more accurate inferences about amphibole-rich rocks from remote observations of the deep crust. By shedding new light on the strength and deformation behavior of amphibole, these data allow us to better predict how continuous deformation may influence the mechanics within zones of earthquake production. The education plan involves Dr. Condit (1) co-teaching a graduate-undergraduate seminar in rock deformation at MIT, (2) acting as a research mentor for several undergraduate researchers, (3) continuing and expanding her geologic outreach on social media, and (4) making geologic presentations at assisted living facilities to disseminate geologic knowledge across generations. Dr. Condit will utilize the state-of-the-art facilities at MIT's rock deformation laboratory to conduct a series of experiments on amphibole, deforming samples at a range of temperatures, pressures, and strain rates representative of those found in the middle to lower crust. With these experimental results, she will determine the deformation mechanisms of amphibole and its rheology under deep crustal conditions. She will then directly tie her observations of these experimentally deformed rocks to naturally deformed amphibole, and collect seismic anisotropy data from the experimentally deformed amphibole samples. This will allow for a direct comparison between deformation mechanism, rock strength, and seismic anisotropy signals produced by the deformed amphibole. These insights will allow geophysicists to better link their remotely sensed observations of seismic anisotropy with the amphibole-rich rocks that produce those signals in the deep crust. Geologists working on naturally deformed amphibole-rich rocks will also be able to use these data to constrain the strength and deformation mechanisms of their rocks.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.

Cailey Condit博士已获得NSF耳朵博士后奖学金，以在马萨诸塞州理工学院执行研究和教育计划。她将调查闪石的方式，闪石是一种常见但知之甚少的地壳中的矿物，当它在高温和压力下变形时表现出色。这项工作将直接扩大我们对深层ca毛剪切区域内连续变形的低估，那里的岩石流动而不是断裂，在俯冲带中，海洋壳降落在大陆下。这项实验性工作旨在限制这些高度变形的，圆形富的区域的强度，并研究其地球物理特性，以便从深层壳的远程观察结果中对地球物理学家对富含闪光剂的岩石进行更准确的推论。通过对闪石的强度和变形行为开发新的启示，这些数据使我们能够更好地预测连续变形如何影响地震产生区域内的力学。该教育计划涉及Condit博士（1）与MIT的岩石变形研究生教育研讨会共同讲授（2），（2）担任几位本科研究人员的研究导师，（3）继续和扩展她在社交媒体上的地质外展览，以及（4）在辅助生活设施中进行地理学的地理学知识，以跨世代进行地理知识。 Condit博士将利用MIT岩石变形实验室中的最先进设施对闪石进行一系列实验，在一系列温度，压力和应变速率下变形样品，代表了中壳中部到较低地壳的样品。通过这些实验结果，她将在深层地壳条件下确定闪石及其流变学的变形机制。然后，她将直接将这些实验变形岩石的观察到自然变形的闪石，并从实验变形的闪石样品中收集地震各向异性数据。这将允许变形机理，岩石强度和地震各向异性信号之间的直接比较。这些见解将使地球物理学家更好地将其对地震各向异性的远程感知的观察与富含闪石的岩石联系起来，这些岩石在深层地壳中产生这些信号。从事自然变形的岩石岩石岩石的地质学家也将能够使用这些数据来限制其岩石的强度和变形机制。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知识分子优点和更广泛影响的评估标准来评估的。