Physical Sciences and Mathematics Commons^™

Using Crystal Zoning, Thermobarometry, And Melts To Elucidate Koma Kulshan’S (Mt. Baker) Transcrustal Magma Storage System, Northern Cascade Arc, Brendan Garvey

WWU Graduate School Collection

Koma Kulshan (Mt. Baker) is classified as a high-threat volcano due to its past eruptive history and its proximity to populations, yet its eruptive products are understudied. Combining mineral chemistry from complexly zoned crystals with thermobarometry and thermodynamic modeling (MELTS) is a powerful way to provide constraints on magmatic processes beneath an active volcano. Up to four populations each of pyroxene, plagioclase, and olivine occur as phenocrysts and crystal clusters in the youngest (9.8 ka) lava flow at Koma Kulshan and represent four co-crystallizing assemblages derived from distinct magmas. These co-crystallizing assemblages are defined by petrologic observations and mineral chemistry …