Collaborative Research: U-Series, Be, Sr, Nd and Pb Isotopic and Trace Element Constraints on Melting and Mass Transfer Processes in Arcs, Philippine Arc System

合作研究：u系、Be、Sr、Nd和Pb同位素及微量元素对电弧熔化和传质过程的约束，菲律宾电弧系统ear -0208095；耳朵- 0207429;耳朵- 0207830 -π:Asmerom;莫里斯;MukasaNet物质在地幔和大陆地壳之间的循环主要发生在弧中。然而，与弧内熔融和质量传递有关的许多过程，例如熔融和挥发脱在从沉积物和蚀变的海洋地壳转移元素中的相对贡献，或地幔楔的动力、减压或通量熔融的相对作用，仍然是谜。该合作提案将重点关注位于菲律宾岛弧构造简单部分的吕宋岛，以比较两个可能具有不同地球化学历史的近距离不同的岛弧设置。假定沉积物贡献的差异使提议的地点成为研究传质过程及其对地幔熔融可能影响的理想场所。结合u系列和Be同位素数据，结合长寿命放射性成因和微量元素数据，将用于研究这些岩石。1)利用4个火山中心（每个弧2个）的主量同位素、痕量同位素和Nd、Sr、Pb同位素资料对火山岩进行特征描述，以圈定每个俯冲带的属性；2)确定沉积物组分的性质和组成及其加入地幔的机制；3)研究动态熔化在电弧中的作用；4)研究u系列核素在岩浆分异过程中的表现。

Collaborative Research: U-Series, Be, Sr, Nd and Pb Isotopic and Trace Element Constraints on Melting and Mass Transfer Processes in Arcs, Philippine Arc SystemEAR-0208095; EAR-0207429; EAR-0207830PIs: Asmerom; Morris; MukasaNet material cycling between the mantle and continental crust occurs primarily in arcs. Many processes related to melting and mass transfer in arcs, such as the relative contributions of melting and devolatilization in transferring elements from sediment and altered oceanic crust or the relative roles of dynamic, decompression or flux melting of the mantle wedge, however, remain enigmatic. This Collaborative proposal will focus on Luzon, located in the tectonically simpler part of the Philippines arc, to compare two different arc settings in close proximity that may have had dissimilar geochemical histories. The presumed difference in sediment contribution makes the proposed site an ideal setting for studying mass transfer processes and their possible effects on mantle melting. Combined U-series and Be isotopic data, in conjunction with long-lived radiogenic and trace element data will be used to study these rocks. The following goals are set forth: 1) to characterize lavas, using major, trace and Nd, Sr and Pb isotopic data, from four volcanic centers, two from each arc in order to delineate attributes of each subduction zone; 2) to determine the nature and composition of the sediment component and the mechanism by which it is added to the mantle; 3) to investigate the role of dynamic melting in arcs; and 4) to investigate the behavior of U-series nuclides during magma differentiation.