Llaima volcano is the second most active volcano in the Andean arc. The volcano also has a history of producing highly explosive mafic eruptions with far reaching deposits, posing a significant hazard to local communities. Recent work suggests that mafic magmas can erupt highly explosively like their silicic counterparts, so studying highly explosive mafic eruptions is crucial to our understanding of mafic eruption dynamics.
Fingerprinting subduction contributions
Explosive mafic eruptions are among Earth's most hazardous volcanic phenomena due to the rapid ascent rates of mafic magma limiting time for early detection and warning systems. To date, work on explosive mafic eruptions has primarily been in the context of conduit and mafic magma fragmentation processes. Through elemental and isotopic characterization and detailed stratigraphic sampling combined with numerical modeling, we examine chemical variations and changes in magma source prior to and during the eruption. Does subduction of the super hydrated crust of the Valdivia Fracture Zone and resulting higher fluid flux in the mantle wedge influence the explosivity potential of the mafic magma?
Eruption of multiple magma bodies
There is increasing recognition that volcanic eruptions can tap multiple magma bodies simultaneously or sequentially rather than erupting from a single magma reservoir. Typically, ignimbrite geochemical studies look at how composition varies throughout the eruption, but this study looks at composition during snapshots in time at various points in the eruption. We do this through careful chemical analysis of multiple single pyroclasts collected from the same sampling horizon. Detailed sampling and statistical validation highlighted chemically heterogeneous pyroclast populations with different mantle fingerprints indicating simultaneous eruption of multiple magma bodies.
Storage and perturbations
Transitions in eruptive style between eruptive periods may result from the bottom up and/or be linked to processes occurring at various levels within the magmatic plumbing system. Minerals and melt inclusions (MI) are erupted time capsules recording information about magmatic processes and perturbations to the magmatic system prior to eruption. In order to link these records with volcanic behavior, we need constraints on where and how the magma was stored.
Magma enclaves
The May 2016 eruption of Sinabung volcano (Indonesia) produced a block and ash flow with andesitic lava and basaltic andesite enclaves. Enclaves can provide a wealth of information about magmatic conditions and system perturbations through petrological investigation.
In this study, I used whole rock and mineral textures and compositions as a "probe" to unravel the evolution and storage of crystal-mush reservoirs and the role of mafic replinshment in eruption longevity. The contrasting textures in enclaves and mineral chemical populations preserve records of shallow and deep crystal-mush storage. Crystal rims and glass compositions record changes in temperature and composition as a mafic magma interacts with the primary reservoir. Contextualizing seismic events before the eruption with petrologic constraints provides strong evidence that the mafic instrusion recharged the primary magma system leading to persistent eruptive activity longer than previous assessments.
Sinabung Volcano, Sumatra, Indonesia - A field season was conducted to collect a spatially and temporarily controlled sample set. These samples will be used to understand the volcanic history at Sinabung Volcano and the implications it may have on future eruptions at the volcano. The video depicts what it was like being a geologist exploring the volcano and collecting rock samples.
Lava and ground ice on Mars
Work during my 2015-2016 NASA Space Grant Internship focused on the correlation between yardangs Medusae Fossae Formation (MFF) and the presence of volcanic rootless cones (VRC) in the Athabasca Valles Flood Lava (AVFL). Time was dedicated to the mosaic tiling of Mars imagery in arcGIS, identifying and outlining VRCs, and measuring yardangs. Our main goal was to continue to train an AI program to identify and highlight VRCs and other crater types on Mars. Our secondary objective was to determine why VRCs only occurred along the edges of the flow where it was in contact with yardangs in the MFF.