Major element, trace element, and H2O abundances in clinopyroxene phenocrysts and equilibrium melts from the Austral Islands

Clinopyroxene phenocrysts crystallized at depth from ocean island basalts record information on magma H2O contents and may be less prone to degassing processes than quenched glasses or melt inclusions formed at lower pressures. Here we report major and trace element and H2O abundances in clinopyroxene phenocrysts from Austral Island basalts, as well as calculated melt compositions in equilibrium with the phenocrysts. These data provide constraints on pre-eruptive magmatic water contents in basaltic magmas from an ocean island setting. This dataset also provides information on the calibration curves used in SIMS analysis of the phenocryst water contents, and estimated cpx/melt partition coefficients used to calculate melt compositions.在深部结晶的单斜辉石斑晶（clinopyroxene phenocrysts）记录了洋岛玄武岩的岩浆水（H₂O）含量信息，且相较于低压环境下形成的淬火玻璃或熔体包裹体，其更不易受脱气作用影响。本文报道了采自奥斯特拉尔群岛玄武岩中单斜辉石斑晶的主量元素、微量元素及水含量数据，同时给出了与该斑晶平衡的熔体成分计算结果。上述数据可为洋岛环境下玄武质岩浆的喷发前岩浆水含量提供约束。本数据集还包含了用于斑晶水含量二次离子质谱（SIMS）分析的校准曲线信息，以及用于熔体成分计算的单斜辉石-熔体分配系数估算值。