Experimental Studies of Calc-Alkaline Magmas

该项目将开展一系列协调的实验、实地和理论研究，旨在了解俯冲带岩浆的过程、形成条件和化学演化。在1 - 3gpa范围内对橄榄岩和类似橄榄岩的块状成分进行实验熔融研究，将研究不同数量的H2O（高达8wt . %）对俯冲带上方地幔楔体熔融的影响。在地壳压力（100 ~ 800 MPa）和饱和水条件下，对玄武岩安山岩、安山岩和安山岩模拟成分进行实验，将为俯冲带岩浆的模式分离结晶提供信息。在美国南喀斯喀特山脉进行的与时空相关的熔岩流的实地研究将为地幔熔融和分离结晶研究提供资料。模拟研究将重现地幔楔中熔体产生的物理条件。这项工作的主要目的是了解控制全球俯冲相关岩浆活动发展的因素。

9706214 Grove This project will carry out a series of coordinated experimental, field and theoretical studies aimed at understanding the processes, conditions of formation and chemical evolution of subduction zone magmas. Experimental melting studies of peridotite and peridotite-analog bulk compositions at 1 to 3 GPa will investigate the effects of variable amounts of H2O (up to 8 wt. %) on the melting of the mantle wedge above the subduction zones. Experiments performed under crustal pressure (100 to 800 MPa) and H2O-saturated conditions on basaltic andesites, andesites and andesite-analog compositions will provide information on model fractional crystallization of subduction zone magams. Field studies in the Southern Cascade Range, U.S.A. to investigate spatially and temporally related lava flows will provide input fo rthe mantle melting and fractional crystallization studies. Modeling studies will reproduce the physical conditions of melt generation in the mantle wedge. The primary objective of this work is to understand factors that control the development of subduction-related magmatism globally.