Highly siderophile element behaviors in large volcanic activities

为了了解与火山活动有关的物质输运机制和元素行为，我们获得了各种洋岛玄武岩和大洋高原玄武岩的高亲铁元素浓度和187Os/188Os同位素数据。为此，我们开发了一种新的分析方法，适用于少量低水平样品。结果表明，导致大火成岩省形成的大型火山活动有效地将高度亲铁元素从地幔预算输送到地壳水平。另一方面，目前的数据集表明，正常条件下的脱气和蚀变过程不能负责将高度亲铁元素大量释放到海洋-大气水库中。

In order to understand the mechanism of material transportation and elemental behaviors associated with large volcanic activities, we obtained highly siderophile element concentrations and 187Os/188Os isotopic data of wide variety of ocean island and oceanic plateau basalts. For this purpose, we developed a new analytical protocol which is suitable for small amounts of low-level samples. The results demonstrated that large volcanic activities leading to the formation of large igneous provinces effectively transport highly siderophile elements from mantle budget to crustal levels. On the other hand, current dataset suggests that degassing and alteration processes in normal conditions cannot be responsible for the significant release of highly siderophile elements into the ocean-atmospheric reservoir.