The Effect of Crystal Plastic Deformation of Quartz in Removing H2O From Fluid Inclusions Containing CO2+H2O

纯二氧化碳流体包裹体通常出现在变质岩中，已知在富含氢的流体存在下结晶。密度与峰值变质条件一致，但它们的组成却不一致。该项目将研究晶体塑性流动和石英动态再结晶过程是否可能导致包裹体中H2O的损失，而CO2仍留在宿主石英中。显示应变梯度的变质岩样品将被用来确定流体包裹体的组成和密度随应变梯度的变化和变形机制的变化。研究结果有望澄清纯CO2包裹体的来源，并为研究高温变形机制提供新的视角。

Pure CO2 fluid inclusions commonly occur in metamorphic rocks which are known to have crystallized in the presence of an H20-rich fluid. Densities are consistent with peak metamorphic conditions, but their composition is not. This project will investigate the possibility that processes attending crystal plastic flow and dynamic recrystallization of quartz may result in loss of H2O from inclusions, with CO2 remaining in the host quartz. Samples of metamorphic rocks showing strain gradients in hand specimen will be utilized to determine the variations of composition and density of fluid inclusions in relation to gradients in strain and variations of deformation mechanisms. Results are expected to clarify origins of pure CO2 inclusions and may provide a new perspective for studies of high temperature deformation mechanisms.