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

9614381斯佩拉这个项目的重点将是限制世界上最活跃的火山之一的岩浆成因过程。埃特纳。具体地说，这项研究将集中于研究碱性富集度与锶和铅同位素组成急剧变化之间的相关性。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不均匀的结果，将使用晶体粒度分布分析(CSD)和斑晶和微斑晶的显微采样相结合的方法对来自六个历史流动的样品进行研究。这项技术将记录材料的同位素组成如何随着晶体大小的变化而变化。如果岩浆化学成分的变化是源区非均质性的结果，斑晶和基质应该有共同的同位素特征。或者，与斑晶的不同晶体大小分布有关的同位素组成的变化将意味着地壳污染作为一种成岩过程的重要性。

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.