Petrological and geochemical data of the 2021 Fagradalsfjall eruption, Iceland

This is the dataset associated with the publication \"The petrology and geochemistry of the 2021 Fagradalsfjall eruption, Iceland: an eruption sourced from multiple, compositionally diverse, near-Moho sills\" by Marshall et al. (2024) in AGU Advances. The dataset includes the results of petrological and geochemical monitoring of the eruption: whole rock major elements, macrocryst-free matrix major and trace elements and radiogenic isotopes, and mineral (olivine, clinopyroxene, plagioclase) major element compositions from the entire 183 day-long eruption.