Geochronological, Isotopic and Petrological Constraints on Magma Dynamics at Mt. Etna

这个项目将集中研究世界上最活跃的火山之一埃特纳火山岩浆成因过程的限制方面。具体来说，该研究将集中于研究碱矿富集与锶和铅同位素组成的剧烈变化之间的相关性。为了评估这些同位素变化是否更合理地解释为地壳污染或地幔非均质性的结果，将结合晶体尺寸分布分析（CSD）和斑晶和微斑晶的微采样对六个历史流的样品进行研究。这项技术将允许记录材料的同位素组成如何随着晶体尺寸的变化而变化。如果岩浆的化学变化是由于岩浆源的非均质性造成的，那么斑晶和基质的同位素特征是相同的。另外，与斑晶不同尺寸分布相关的同位素组成的变化可能暗示地壳污染作为一个岩石形成过程的重要性。

9614381 Spera This project will focus on constraining aspects of the magma geneses processes at one of the most active volcanoes in the world, Mt. Etna. Specifically, the study will concentrate on investigating correlations between alkali enrichments and dramatic changes in Sr and Pb isotopic composition. To assess whether these isotopic changes are more reasonably interpreted as the result of crustal contamination or mantle heterogeneity, samples from six historical flows will be studied with a combination of crystal size distribution analysis (CSD) and microsampling of phenocrysts and microphenocrysts. This technique will allow the documentation of how the isotopic composition of the materials change with crystal size. Common isotopic signatures are expected for phenocrysts and matrix if the variations in the chemistry of the magmas is the result of heterogeneity in the source. Alternatively, changes in isotopic composition associated with different crystal size distribution of phenocrysts would imply the importance of crustal contamination as a petrogenetic process.