Magma Loading and Barrovian Metamorphism: A Critical Analysis, Nason Terrane, Washington

这项研究计划结合了华盛顿州内逊地的野外工作、结构测量和解释、岩石学、相岩石学、热气压测定和同位素年龄测定。本研究的目的是对最近提出的构造模型——岩浆负荷——所依据的实地证据进行批判性的检验。该模型揭示了成岩作用、变质作用和变形在时间上的一致性，岩体与压力和温度的分布和历史的空间关系，以及产生和消除陡压梯度的弯曲事件。该研究对大体积岩浆弧的造壳和变质作用具有重要意义。

9304021 Evans This research proposal combines field work, structural measurements and interpretation, petrography, phase petrology, thermobarometry, and isotopic age determinations in the Nason Terrane of the state of Washington. The purpose of the study is to examine critically the field evidence on which the recently proposed tectonic model termed magma loading is based. The model implies coincidences in timing between plutonism, metamorphism and deformation, spatial relationships among plutons and the distribution and history or pressure and temperature, and flexuring events producing and then eliminating steep baric gradients. The proposed research has major implications for crust-building and metamorphic processes in large-volume magmatic arcs.