Investigating Magma Chamber Evolution Using Crystal Isotope Stratigraphy

9805023戴维森这个项目将使用传统的显微取样技术和新的原位激光消融技术来获得高精度和高分辨率的矿物相同位素数据，从而显著提高我们对岩浆分异的理解。晶体同位素地层学(CIS)的简单原理是，生长在一个不同的开放岩浆系统中的晶体记录了它们结晶所来自的液体的同位素组成的长期变化。当结合结构和矿物成分数据时，可以重建详细的分异历史。这一理论将在两个密切相关的研究中得到发展：1)苏格兰罗姆一个受污染和重新注入的岩浆室的层状堆积序列的研究，以及2)新西兰恩高鲁霍火山开放系统分化的年代喷发产物的详细研究。第一项研究将允许研究比火山岩套所代表的更漫长和更完整的分化史，而第二项研究凭借极好的时间限制，可能能够通过时间对开放系统的分异进行校准。

9805023DavidsonThis project will use both conventional microsampling techniques, together with new in situ laser ablation techniques to obtain high precision and resolution isotope data on mineral phases, and to thereby significantly improve our understanding of magmatic differentiation. The simple principle of crystal isotope stratigraphy (CIS) is that crystals growing in a differentiating open magma system record secular changes in the isotope composition of the liquid from which they crystallize. When combined with textural and mineral composition data a detailed history of differentiation can be reconstructed. This philosophy will be developed in two closely related investigations; 1) an examination of the layered cumulate sequence from a contaminated and recharged magma chamber at Rhum, Scotland, and 2) detailed studies of the dated eruption products of open system differentiation at Ngauruhoe volcano, New Zealand. The first study will allow examination of a far more protracted and complete differentiation history than is represented by volcanic rock suites, while the second, by virtue of the excellent time constraints, may enable calibration of open system differentiation through time.