Collaborative Research: Oxygen Isotope Constraints on Major Element Heterogeneity in the Mantle Beneath Mid-Ocean Ridges

虽然洋中脊玄武岩提供了广泛分布的海洋上地幔样本，这些岩石的化学成分可能限制了地幔的温度和组成，但解释这些限制需要使用岩石成因模型进行反演，该模型指定了地幔矿物学、温度、地球化学和动力学。这些玄武岩中的氧同位素变化有可能增加重要的新限制，因为俯冲洋壳的氧同位素组成与普通地幔橄榄岩的氧同位素组成不同，因此地壳向上地壳的俯冲可以形成既富含玄武岩成分又富含沉积成分的域，而在三角洲018中则是异常的。详细研究了洋中脊玄武岩的结晶分异、地壳同化和亚固相蚀变对三角洲018的影响。

While mid-ocean ridge basalts provide wide-spread samples of the oceanic upper mantle and the chemistry of these rocks potentially constrains mantle temperature and composition, interpreting these constraints requires inversion using petrogenetic models that specify mangle mineralogy, temperature, geochemistry, and dynamics. Oxygen-isotope variations in these basalts have the potential to add important new constraints because oxygen-isotope composition of subducted oceanic crust differs from that of common mantle peridotites such that subduction of crust into the uppermantle can create domains that are both compositionally compositionally enriched in basaltic and sedimentary components and anomalous in delta 018. Detailed sutdies of suites selected to examine the influence of crystallization-differentiation, crustl assimilation, and sub-solidus alteration on the delta 018 of mid-ocean ridge basalts.