Application of MELTS program to Fractional Crystallization of Low Alumina Alkaline Magma in Jeju Volcanic Island

Abstract Jeju Volcanic Island is the largest island in South Korea which is known as the continental shelf intraplate volcanic island. MELTS, one of the powerful programs utilizing for modeling magmatic evolution processes, is applied to simulate fractional crystallization process of low-alumina alkaline volcanic rock suite in Jeju Island. At many isobaric pressure conditions from 2.0 GPa to 0.1 GPa as well as different oxygen fugacities (fO2) from FMQ-3 to FMQ + 3 and H2O content, MELTS modeling were conducted as various calculations. The results demonstrate that the most suitable fractionation model for Jeju low-alumina alkaline magma would occur from 0.2 GPa to 0.1 GPa with oxygen fugacity FMQ buffer. These contain 0.5 wt.% H2O in the system leading to more consistent with evolution trending of as well as mineral composition in natural rock suite on Jeju Island. Although MELTS still possesses several limitations in the stability of calibration such as spinel overestimation as well as a lack of experiments for hydrous minerals which have been renovated, MELTS exhibits its affection on temperature and pressure prediction as well as assess other factor of fractional crystallization process on Jeju Island. Consequently, to evaluate a magmatic process in a particular region, it would be better to combine MELTS with other analyses rather than operating independently.