Planetary volcanism, Volcanic fluid dynamics, Icy satellite geology
In my research I strive to understand the mechanisms of formation of geologic (especially volcanic) features on the Earth and other planetary bodies. I am particularly interested in the physics of eruptive processes, and the influence that planetary environment has on the style of eruption and resulting landform. I typically integrate spacecraft image analysis, numerical modeling of volcanic processes, and field studies of terrestrial analog features in order to understand the evolution of planetary surfaces.
Investigation of lava-H2O interactions in Iceland and on Mars. Lava flowing over a water- or ice-rich surface can induce explosive vaporization of the water, leading to the formation of small rootless volcanic cones. The size, spacing and location of such cones observed in spacecraft data, together with modeling the explosion mechanism, can yield information on the distribution of subsurface ice on Mars.
Lava fluid dynamics and heat transfer: the role of thermomechanical erosion. Large, sinuous, volcanic channels found on the Moon, Venus, and Mars may have formed when lava melted and entrenched into the underlying ground surface. On Earth, such erosion is seen on a small scale (for example in Hawaiian lava tubes), so there is only a poor understanding of how these much larger planetary channels may form. I have been performing computational fluid dynamic modeling to determine the eruption conditions required to produce terrestrial and planetary channels.
Debris Flow Modeling. Mixtures of particulate materials and water can generate rapidly advancing debris flows. Such mechanisms of emplacement are relevant to volcanic lahars on Earth and Mars, and rampart crater ejecta slurries on Mars. By developing mathematical treatments of the emplacement processes and applying them to digital representations of the surface topography (DEMs), it is possible to improve lahar hazard assessment on Earth, and to understand rampart crater formation on Mars.
Cryomagmatism on Europa. Europa, one of the icy satellites of Jupiter, displays a wide variety of features indicative of a dynamic interior. I have been studying Europan geology to determine the role that icy magmatism or volcanism may have played. Cryomagmas consisting of mixtures of water, ice and possible contaminants may have moved through Europa's icy shell and erupted onto the surface. Numerical modeling of the associated heat and mass transfer can provide clues as to the presence and extent of liquid water inside Europa.