Fluid-rock interactions and lithospheric deformation
Understanding the solid-Earth materials and processes that underpin geological hazards at volcanoes and fault zones is a central challenge in Earth Sciences. My interdisciplinary solid-Earth geophysics program addresses this by integrating petrophysical and geomechanical rock properties measured in the lab with observational-scale geophysical and space-borne data and models. This approach advances our understanding of the fundamental processes driving geohazards, and translates that understanding into tangible outputs for geohazard assessment. The central question driving my research is: how do fluid-rock interactions influence lithospheric deformation?
Volcano deformation and hazards
Lab scale
Under this theme, my research investigates a set of questions central to understanding volcanic systems: How does hydrothermal alteration change the physical and chemical properties of volcanic rocks? How do these changes affect edifice strength and stability? How would these geological changes manifest in geophysical data, and how can that data be used to interpret the state of a volcano at depth? To address these questions, I combine experimental rock physics with petrologic and geochemical measurements on lavas and tuffs. Work on Mt. Taranaki and Whakaari (White Island) has shown how alteration changes elastic wave velocity, magnetization, and poroelastic behavior, and what these changes mean for dome and edifice stability. This provides a physical basis for interpreting geophysical signals, including magnetic anomalies, seismic velocity changes, and permeability contrasts, in terms of underlying rock alteration state.
Observational scale
This theme also asks how laboratory-derived understanding of rock alteration can be connected to field-scale monitoring and models to better understand volcanic deformation and hazard. At Whakaari, this has meant using InSAR time-series analysis to track ground deformation across multiple eruptive cycles, and connecting the resulting deformation patterns to the subsurface alteration and pressurization processes identified in the lab. It has also meant incorporating subsurface heterogeneity, including alteration-driven strength variability, into scenario-based slope stability assessments, applied at Augustine Volcano, Alaska, to evaluate flank and edifice collapse hazard. This work is ongoing and continues to explore how rock-scale alteration mechanisms scale up to edifice-scale deformation and hazard.
Fault-slip behavior
Lab scale
Under this theme, my research asks how fluid-rock interactions control the physical properties of fault rocks, and what that means for how faults accommodate deformation. On the Alpine Fault, New Zealand, a major plate-boundary fault, this work has shown how cataclasite composition and fluid-driven alteration govern elastic wave velocity and compliance, and how persistent compliance contrasts help localize deformation along the fault. This theme extends to a broader question: what mechanisms cause some patches on a fault to slip seismically, producing earthquakes, while adjacent patches creep aseismically? A current NSF-funded collaboration investigates this question on oceanic transform faults, using petrophysical measurements to constrain how earth materials modulate the balance of seismic and aseismic slip, and how this combination accommodates plate motion.
Observational scale
A continuing direction of this theme is connecting these lab-based constraints to observational-scale fault behavior, linking rock properties to geodetic and seismic signatures of slip in the field.
Sustainable energy transition
The same fluid-rock interaction framework that underpins my hazard research also applies to energy-transition problems such as carbon mineralization and hydrogen storage. Under this theme, my research investigates how naturally occurring rock-fluid processes can be simulated, enhanced, or utilized to develop environmental solutions: How can we simulate the rock-fluid interactions occurring in nature to advance our understanding of the solid Earth and inform strategies such as carbon sequestration? How do these interactions change the physical and chemical properties of rocks, and how do those changes manifest in geophysical data? My research in this space has involved experimentally reacting basalt with CO2-rich fluids to characterize the dissolution and secondary mineral precipitation that drive natural carbon mineralization, laying groundwork for using basalt reservoirs as carbon sequestration targets.
