Mobility and Storage of Volatiles in Forearcs: The Metamorphic Record

9805050 贝布 本研究将探讨深加积岩石中挥发性组分的挥发或保留程度作为前弧深部P-T历史的函数。这一综合领域，岩石学和地球化学工作将集中在套房，以前详细的岩石学和热年代学研究提供了制约逆冲和逆行变质演化，并将集中在选定的voaltile组件的俯冲循环预计是重要的。不同程度的挥发损失的证据将与目前的矿物学和推断的变质反应历史。该研究还将提供有关低T、高P/T变质套系保存高P/T流体的同位素组成和来源、深孔隙水俯冲的程度以及前弧深部流体流动性的规模的记录的程度的信息。实地区域将包括西部巴哈地体和Franciscan综合体的部分地区。第二项任务将在海岸山脉的选定曝光中进行研究。

9805050 Bebout This research will examine the extents of devolatilization or retention of volatile components in deeply accreted rocks as functions of P-T history deep in forearcs. This integrated field, petrologic and geochemical work will concentrate on suites for which previous detailed petrologic and thermochronological studies have provided constraints on prograde and retrograde metamoprhic evolution, and will focus on selected voaltile components for which subduction cycling is expected to be important. The evidence for varying degrees of volatile loss will be linked with present mineraology and inferred prograde metamorphic reaction histories. The reserach will also provide information regarding the degree to which low-T, high-P/T metamorphic suites preserve a record of the isotopic compositions and sources of high-P/T fluids, the extents of deep pore water subduction, and the scales of fluid mobility at depth in forearcs. The field areas will include the Western Baja Terrane and parts of the Fransciscan Complex. The second task will be studied in selected exposures in the Coast Ranges.