Investigation ofFluid Flow in an Ancient Subduction Zone

变形的性质决定了加积的基础 楔状体可能涉及大量的流体输送， 二氧化硅和其他成分，脆性裂纹密封脉纹， 岩石结构如解理。 然而， 流体相互作用的大小以及 它们是否有效是非常有争议的。 这个项目 将检查其分布，方向，几何形状， 出露较好石英脉结构和地球化学特征 在Afognak岛上的一个被广泛了解的前弧复合体， 阿拉斯加 与壁内体积变化的测量相结合 岩石和氧同位素分析 将重建埋藏在8 - 12公里深处的岩石， 用于推断二氧化硅的运输机制和 底部附近流体流动的范围和性质 加积楔 结果将与研究相关 加积，楔形发展和研究 岩石变形组构的成因

The nature of deformation hear the base of accretionary wedges likely involves extensive transport by fluids of silica and other components, brittle crack-seal veining and rock fabrics such as cleavage. However, estimates of the magnitude of fluid interactions and the scale over which they are operative is highly controversial. This project will examine the distribution, orientation, geometry, texture and geochemistry of quartz veins in a well-exposed and well-understood forearc complex on Afognak Island, Alaska. Coupled with measurements of volume change in wall rocks and oxygen isotopic analyses the plumbing system in rocks buried to depths of 8-12km will be reconstructed and used to infer the mechanisms of silica transport and the extent and nature of fluid flow near the base on an accretionary wedge. Results will be relevant to the study of accretionary, wedge development and to the study of the origins of rock deformation fabrics.