My work is focused on what the compositions and textures of minerals and glasses can tell us about the conditions in the Earth that lead to natural disasters. I am particularly interested in applying diffusion models to understand the timescales that lead to volcanic eruptions and seismic events.

Reliability of quartz-hosted melt inclusion compositions: Hydrogen isotopes, volatile contents, and trace elements reveal discrete pre-eruptive magma bodies in the Highland Range, NV

Hickernell, Pamukçu, & Monteleone (in review, Science Advances)

High-silica magmas (≥68 wt. % SiO₂) have produced some of the largest and most impactful volcanic eruptions in Earth’s history. Quartz-hosted melt inclusions can provide critical insights into the architecture, evolution, and eruption of silicic magmas, however the reliability of mineral-hosted melt inclusion compositions has been questioned due to potential post-entrapment modification of inclusions via diffusive exchange. We demonstrate that with careful sample selection, both naturally glassy and experimentally homogenized quartz-hosted melt inclusions can retain meaningful pre-eruptive signatures and provide useful insights into pre-eruptive magmatic conditions. We also show that hydrogen isotope measurements and detailed descriptions of melt inclusion geometries are particularly critical for identifying post-entrapment diffusive exchange in melt inclusions, whether it is due to natural or experimental processes. Finally, combining data from measurements of quartz-hosted melt inclusion hydrogen isotopes, trace elements, volatiles, and geometries, we fingerprint multiple discrete rhyolite magma reservoirs in the Highland Range Volcanic Sequence (NV, USA).

Architecture of an eruptible silicic magmatic system: pre-eruptive storage depths of high-silica rhyolites from the Highland Range, NV

In prep.

We characterize the pre-eruptive storage depths of high-silica rhyolites of the Highland Range Volcanic Sequence with geobarometry and utilize glass trace element geochemistry to evaluate the architectural complexity of the pre-eruptive storage region(s). We find that the high-silica rhyolites were all stored at similar upper crustal depths prior to eruption, however trace element geochemistry indicates these silicic magmas remained separate and distinct from one another, suggesting a complex storage configuration. The eruptible rhyolitic magma bodies were discrete in time and/or space. We find that machine learning geobarometry can result in highly uncertain pressure estimates, however both Rhyolite-MELTS and melt inclusion volatile saturation pressure estimates are consistent with storage of high-silica rhyolites within or near depths consistent with the most silicic portions of the neighboring Searchlight Pluton. The Searchlight Pluton has been suggested as the cogenetic intrusive complement to the Highland Range Volcanic Sequence (Bachl et al. 2001; Colombini et al. 2011; Wallrich et al. 2023; Gualda et al. 2024; and others), and our results are consistent with this proposed relationship. We also suggest that many of the quartz-hosted melt inclusions were likely entrapped within a mush in the Searchlight Pluton prior to melt extraction. This work bolsters the volcano-pluton connection model for the Searchlight Magmatic System.

Longevity of highly silicic, eruptible magma bodies: a diffusion chronometry perspective

In prep.

Mineral compositions and zoning textures can record changes in crystallization conditions and reflect the timescales over which geologic processes occur. Diffusion is a thermally-activated process, and we can leverage the rate of diffusive reequilibration of an element or molecule between compositional zones to determine the timescale over which that mineral was held at elevated temperatures. When a zoned mineral is held at elevated temperatures, its compositional zones will progressively “blur”. We can model this “blurred” compositional profile to determine the timescales over which the mineral was at high temperatures. In a magma, we can interpret the period of time over which a mineral is held at high temperatures to be when that magma was considered eruptible.

We leverage Ti zoning in quartz from rhyolites of the Miocene-age Highland Range, NV, to evaluate the timescales over which rhyolites remained eruptible in the Searchlight Magmatic System. In the Highland Range rhyolites, only the fastest published Ti-in-quartz diffusivities produce timescales consistent with the known longevity of the Searchlight Magmatic System based on zircon geochronology and thermal modeling perspectives (see Pamukçu, Hickernell, et al. 2025). We find that pre-eruptive storage of rhyolites was relatively short-lived prior to eruptions in the Highland Range, on the order of decades. Our results have implications for understanding the pace at which eruptible silicic magmas accumulate and destabilize in the upper crust prior to volcanic eruptions.

Timescales of seismic cycles and dehydration reactions in subduction zones recorded by compositional zoning and diffusion in epidote

For my postdoctoral research, I am bringing my experience and interest in volcanic mineral diffusion chronometry into the metamorphic realm. I am conducting diffusion experiments on epidote and clinozoisite with Cailey Condit at University of Washington and Hanna Shamloo at Central Washington University to develop a chronometer to estimate the timescales of dehydration reactions and seismic cycles along the subduction interface. While diffusion chronometry is fairly commonplace in an igneous petrologist’s toolbox, it is less frequently utilized in metamorphic rocks. The goal of my postdoctoral work is to help bridge some of the gaps between the igneous and metamorphic communities and develop a framework for using epidote to monitor the timescales of tectonic and metamorphic processes.