Mineral-Specific Iron Oxidation States and Oxygen Fugacity of Mantle Xenoliths from Jeju and Baengnyeong Islands

This study investigated the iron oxidation states and redox characteristics of spinel lherzolite xenoliths from Jeju and Baengnyeong Islands, South Korea, using electron probe microanalysis (EPMA) and Mössbauer spectroscopy. Mössbauer spectroscopy was used to characterize the Fe 2+ and Fe 3+ distributions in individual minerals and determine the Fe 3+ /ΣFe ratios in spinel, while EPMA provided the mineral compositions required for oxygen fugacity calculations. The calculated oxygen fugacity values ranged from − 0.84 to -0.12 log units relative to the fayalite–magnetite–quartz (FMQ) buffer, revealing differences in redox conditions among the investigated samples. These findings provide insights into the mineral-specific iron oxidation states and redox characteristics of mantle xenoliths from the two regions.