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

9304021埃文斯这项研究提案结合了华盛顿州纳森地体的野外工作、构造测量和解释、岩石学、相岩石学、温压测量和同位素年龄测定。这项研究的目的是批判性地检验最近提出的被称为岩浆加载的构造模型所基于的现场证据。该模型暗示了深成作用、变质作用和变形之间的时间上的重合，深成岩体与分布和历史或压力和温度之间的空间关系，以及挠曲事件产生并随后消除陡峭的压力梯度。这项研究对大体积岩浆弧中的地壳建造和变质过程具有重要意义。

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.