June Cho

My research to date has primarily involved studying mafic layered intrusions (MLI) and in particular, late-stage magmatic processes that occur during their crystallization. MLI are excellent natural laboratories for understanding important petrologic concepts, especially in closed-system intrusions where slow-cooling with little interaction can be achieved.

My BSc research, also at UBC, focused on symplectites (late-stage reactive microstructures) in the Kiglapait layered intrusion (Labrador, Canada) in order to decipher their compositional and textural relationships and to tease out the chemical evolution of interstitial liquids.

My MSc project aims to establish the variability in lead isotopic compositions of plagioclase from the ~56 Ma Skaergaard intrusion (E. Greenland) by laser ablation ICP-MS. The trace element and Pb isotope systematics will be used to constrain the parent magma and mantle source compositions and to determine the extent and nature of crustal contamination prior to emplacement. Thanks to the closed-system nature of the intrusion and its magnificent exposure and preservation of the complete sequence of rocks, the Skaergaard has long served as the testing ground for many magmatic processes.

It is exciting to join the ranks of scientists who devote their time and effort to unraveling the many questions we still have about layered intrusions... some of the big picture questions that still remain include (from the Penrose conference report; Boudreau et al. 2016):

• What are the timescales of emplacement and cooling of LMI?
• What is the physical nature of a magma chamber?
• Have large volume mafic magma chambers ever existed?
• How do monomineralic layers form in LMI?
• How much crustal contamination occurs in LMI magmatism?
• In what tectonic settings are LMI likely to form?
•​ What can we learn from the material sciences about the cooling and solidification of layered cumulates?