Professor of Volcanology
I study active volcano systems. My principal research philosophy is to address important problems in volcanology by applying a multi-disciplinary and integrated approach. Some examples of my approach include the role of calderas in certain types of ore deposits, the relationship of degassing to other geophysical parameters of volcano unrest, and the role played by volcanism in terms of human health.
During the past five years, my group has tackled the important problem of caldera evolution and caldera structure. We have been employing a combination of field and experimental techniques to elucidate the subsurface structure of calderas. By examining partly eroded calderas in the field as well as surface sections and cross sections of sandbox experiments, we have been able to gain insight into the diversity of structures formed during caldera development.
The physical processes which occur during degassing and within the conduit system of a volcano are important for eruption style and periodicity, as well as for changing pressure conditions in the magma conduit-reservoir system. I have examined various problems such as the role of diffuse degassing and passive degassing at the surface and within the conduit system itself. These studies typically integrate petrology, textural analysis of rocks, and gas remote sensing.
An important development in my research during the last five years has been the inclusion of experimental approaches and methods to help solve the problems I am studying. Examples include experimental density currents as an analogue for pyroclastic flows, sandbox experiments to model caldera subsidence, and piston-cylinder experiments to investigate boron behavior in vapor-rich and liquid-rich fluids.