Hydrous Phases in Subduction Zone Settings: Effects on Sediment Physical Properties and Microfabric

沉积物埋藏过程中发生的脱水和压实等伴生过程受到沉积物组成和微结构（即粒间相互作用）的强烈影响。为了更好地理解俯冲带背景下的流体流动、增生、底板和断裂，需要改进这两个过程的记录。Drs。Tribble和Wilkens将扩展巴巴多斯吸积棱镜的早期工作，包括对南开海槽DSDP/ODP岩心的研究。x射线衍射将用于确定几个地点样品的矿物学，以建立统一的存档数据集。将特别强调确定蒙脱石和生物成因二氧化硅的丰度和成岩蚀变。将追踪到火山灰向蒙脱石的渐进蚀变过程。微结构研究将使用扫描和透射电子显微镜进行，目的是量化结构随深度，组成和构造背景的变化。

The companion processes of dewatering and compaction that occur during sediment burial are strongly influenced by sediment composition and micro-fabric (i.e., grain-to-grain interactions). Improved documentation of these two processes is needed to gain better understanding of fluid flow, accretion, underplating and faulting in subduction zone settings. Drs. Tribble and Wilkens will extend earlier work from the Barbados accretionary prism to include studies of DSDP/ODP cores from Nankai Trough. X-ray diffraction will be used to determine the mineralogy of samples at several locations to develop a uniformly archived data set. Special emphasis will be placed on determining the abundances and diagenetic alteration of smectite and biogenic silica. Progressive alteration of volcanic ash to smectite will be traced. Microfabric studies will be conducted with both scanning and transmission electron microscopy, with the intention of quantifying changes in fabric with depth, composition and tectonic setting.