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

摘要：规划拨款将用于调查阿迪朗达克山脉各种高级变质岩中的橄榄石微结构。阿迪朗达克的变质岩和火成岩记录了广泛的压力、温度和变形制度，通过这些记录，应该有可能在一系列条件下记录碱性长石的结构和化学行为。通过揭示化学交换的细节和晶体内微孔网络的可能发展，本研究将针对碱性长石在稳定同位素交换、辐射测年、地质测温、地质压力测量、风化、渗透率发展、变形机制等研究中可能存在的限制。来自阿迪朗达克地区精心挑选的样品将通过光学显微镜进行分析，光学显微镜是PI开发的一种独特的蚀刻/扫描电子显微镜技术，最终将通过透射电子显微镜和电子探针进行分析。部分工作将在家庭机构和/或附近的实验室进行，而大部分工作将在爱丁堡大学(在一个地点提供所有必要的设施)在PI的初级教员休假期间完成。一旦这些方法的可行性得到测试，PI将设计一项对阿迪朗达克山脉一个或多个地区的密集研究，并向EAR提交一份完整的研究提案。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