The Flux of Volatiles from Active MARGINS: the Central American Volcanic Arc

0079402 Fischer在俯冲带中，物质从俯冲板块的沉积物转移到弧岩浆中已经被化学示踪剂所确定，如铍和硼。 近年来，在了解俯冲带中的元素旋回和这些旋回的时间尺度方面取得了重大进展，其目标是获得活动边缘的元素收支。 大量的详细的地球化学资料，可用于弧岩浆的立场，相反，非常有限的详细资料，可用于挥发性排放从活跃的边缘火山。 挥发岩在俯冲带元素迁移过程中起着关键作用。 尽管它们很重要，但相对而言，人们对俯冲带中挥发物的最终来源知之甚少。 对任何活动俯冲带的挥发性收支所知更少，本项目的目标是对中美洲火山弧沿线沿着的3-4座活火山的挥发性排放源和这些挥发性物质向大气的通量进行详细、系统的研究。 私家侦探将试图确定二氧化碳、水、氮和惰性气体的来源及其向大气的通量。 中美洲火山弧是世界上进行此类研究的最佳地点之一，因为可以获得大量关于岩浆的地球化学信息，记录的流体贡献量沿弧的走向沿着变化，地壳污染相对较小且受到很好的限制。 这项研究是针对这3-4座火山的“试点研究”，目的是测试挥发物来源与地球化学确定的岩浆来源是否存在相关性。

0079402FischerIn a subduction zone, the material transfer from sediments of the subducting plate into arc magmas has been identified by chemical tracers, such as Berillium and Boron. In recent years, significant progress has been made towards understanding the element cycles in subduction zones and the time-scales these cycles operate on with the goal of arriving at element budgets of active margins. The vast amount of detailed geochemical information available for arc magmas stands in contrast to the very limited detailed information available for volatile discharges from active margin volcanoes. Volatiltes play a pivotal role in element transfers occurring at subduction zones. Despite their importance, comparatively little is known about the ultimate sources of the volatiles in subduction zones. Even less is known about the volatile budgets of any active subduction zone.The goal of this project is to perform a detailed, systematic study of the sources of volatile discharges and the fluxes of these volatiles to the atmosphere at 3-4 active volcanoes along the Central American Volcanic Arc. The P.I. will attempt to determine the sources of carbon dioxide, water, nitrogen and noble gases and their fluxes to the atmosphere. The Central American Volcanic Arc is one of the best places in the world for such a study because a vast amount of geochemical information on the magmas is available, the amount of fluid contributions is documented to vary along strike of the arc, and crustal contamination is relatively minor and quite well constrained. The study is a "pilot study" targeting these 3-4 volcanoes in order to test whether there is a correlation regarding the sources of volatiles with the sources of the magmas as identified geochemically.***