EAR-PF: Experimental Investigation of the kinetics and mechanics of reaction-induced strain localization

Eric Goergen博士被授予美国国家科学基金会地球科学博士后奖学金，以开发布朗大学的研究和教育综合计划。该项目的目标是重点探索岩石中反应引起的应变局部化发展的动力学驱动力和机制相互作用。本项目旨在通过对橄榄岩块体组成岩石进行一系列变形实验，研究反应与变形同时发生的过程。这些实验旨在通过三种方法探索应变局部化：1)研究已知的反应速率与应变速率之间的正相关关系；2)通过增加有限应变量的一系列实验，表征了与反应引起的应变局部化相关的微观结构的时间依赖演化；3)通过改变初始材料中存在的相的模态量来研究体组成对反应进展和局部化的影响。实验将通过化学和晶体学分析来分析微观结构的演变，从而建立实验内部和实验之间的动力学和力学历史模型。此外，为这些实验选择的橄榄岩化学系统和压力-温度也将为上地幔在演化的整体组成和相组合的背景下提供基本的流变学数据。该项目还旨在通过整合本科研究，将强大的教育成分纳入其中。Goergen博士开发了两个适合本科水平的独立项目，也将为上述研究目标做出巨大贡献。这些项目将为年轻地球科学家的智力发展奠定坚实的研究基础，并通过指导本科生论文获得必要的综合研究和教学经验，从而进一步促进Goergen博士的专业发展。

Dr. Eric Goergen is awarded an NSF Earth Sciences Postdoctoral Fellowship to develop an integrated program of research and education at Brown University. The goal of this project is focused on exploring the kinetic driving forces and mechanistic interactions fundamental to the development of reaction-induced strain localization in rocks. This project aims to investigate simultaneous reaction and deformation processes through a series of deformation experiments carried out on rocks of lherzolite bulk composition. These experiments are designed to explore strain localization through three approaches: 1) investigating the known positive correlation between reaction rate and strain rate; 2) characterizing the time dependent evolution of microstructures associated with reaction-induced strain localization through a series of experiments carried out to increasing amounts of finite strain; and 3) investigating the effect of bulk composition on the progress of reaction and localization by varying modal amounts of phases present in starting materials. Experiments will be analyzed by focusing on the microstructural evolution through chemical and crystallographic analysis to develop models of the kinetic and mechanic history within and between experiments. In addition, the choice of the lherzolite chemical system and pressure-temperatures for these experiments will also provide fundamental rheologic data on the upper mantle in the context of evolving bulk composition and phase assemblages.This project also aims to incorporate a strong educational component through the integration of undergraduate research. Dr. Goergen has developed two independent projects that are appropriate for the undergraduate level and will also contribute strongly to the research objectives stated above. These projects will both further the intellectual development of young geoscientists by laying a strong foundation in sound research as well as, further the professional development of Dr. Goergen by gaining necessary experience in the integration research and teaching through the advising of undergraduate theses.