Determination of Volcanic Flux Rates and Application to Understanding Regional Geochemical Trends and Element Mass Balances in Central America

迈克尔·j·卡尔关于俯冲过程性质的几个重要问题需要从现有的定性俯冲信号（如Ba/La和10Be/9Be）过渡到定量通量（如以gm/单位弧长/年为单位的Ba通量）。这是通过使用40Ar/39Ar测年技术来测量中美洲几个大型火山中心的较老单位的年龄来完成的。这些新数据，加上先前确定的体积测量，可以确定弧不同部分的平均火山通量率。将火山通量率与区域地球化学数据相结合，可以对元素通量进行估计。根据这些综合数据，几个主要问题正在得到解决，包括中美洲俯冲信号沿走向变化的物理原因，通过中美洲弧循环的元素的质量平衡，以及通过俯冲传递到深部地幔的不相容元素的数量。

EAR-0203388 Michael J. Carr Several important questions about the nature of the subduction process require a transition from existing qualitative subduction signals, such as Ba/La and 10Be/9Be, to quantitative fluxes such as Ba flux in gm/unit arc length/yr. This is accomplished by employing 40Ar/39Ar dating techniques to measure the ages of the older units in several large Central American volcanic centers. These new data, along with previously determined volume measurements, enable the determination of average volcanic flux rates for different segments of the arc. Integrating volcanic flux rates with regional geochemical data allows an estimate of element fluxes to be made. From these integrated data several major problems are being addressed, including the physical cause of along-strike variations in subduction signal in Central America, the mass balance of elements cycling through the Central American arc, and the quantity of incompatible elements that are delivered to the deep mantle through subduction.