RPG: Application of Perthitic Microtexture to the Study of High Grade Terranes: Examples from the Adirondack Mountains, New York

摘要：计划拨款将用于调查阿迪朗达克山脉各种高品位变质岩中的斑岩微织构。阿迪朗达克山脉的变质岩和火成岩记录了广泛的压力、温度和变形机制，通过充分记录这些岩石，应该有可能记录碱长石在各种条件下的结构和化学行为。通过揭示晶体内微孔网络的化学交换和可能发育的细节，本研究将针对碱长石在稳定同位素交换、放射性定年、地热、气压、风化、渗透性发育、变形机制等研究中可能存在的局限性。来自阿迪朗达克地区精心挑选的样品将通过光学显微镜（PI开发的独特蚀刻/扫描电镜技术）进行分析，最终通过TEM和电子显微探针进行分析。部分工作将在本地机构和/或附近的实验室进行，而重要的部分将在PI的初级教师休假期间在爱丁堡大学完成（所有必要的设施都在一个地方）。一旦测试了这些方法的可行性，PI将对阿迪朗达克地区的一个或多个地区进行深入研究，并向EAR提交一份完整的研究计划。9

Abstract: The planning grant will be used to survey perthite microtextues from a variety of high-grade metamorphic rocks in the Adirondack Mountains. By relying on the well-documented metamorphic and igneous rocks of the Adirondacks, which record a wide range of pressure, temperature, and deformational regimes, it should be possible to document the textural and chemical behavior of alkali feldspars over a range of conditions. By revealing the details of chemical exchange and possible development of intracrystalline networks of micropores, this study will target possible limitations on the use of alkali feldspars in studies of stable isotope exchange, radiometric dating, geothermometry, geobarometry, weathering, permeability development, deformation mechanisms, etc. Samples from carefully selected localities in the Adirondacks will be analyzed by optical microscopy, a unique etching/SEM technique developed by the PI, and ultimately by TEM and electron microprobe. Part of the work will be carried out at the home institution and/or nearby labs, while a significant part will be done at Edinburgh University (where all necessary facilities are available at one location) during the PI's junior faculty leave. Once the feasibility of the methods has been tested, the PI will design an intensive study of one or more areas in the Adirondacks, and submit a full research proposal to EAR. 9