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Bill Evans, PhD

My research focused on volcanic volatiles and water-rock interaction in geothermal systems. 

Gases are an important factor in volcanic hazards because of their role in driving explosive eruptions and their intrinsic toxicity.  Part of the answer to, “What could happen?” at a restless volcano comes from gas studies.  The mechanism of gas generation at depth and gas migration up through boiling hydrothermal systems, cold groundwaters, and the unsaturated zone are all complex processes that are only partly understood.  The goal of my research is to use gas flux, composition, and isotope values to refine our general understanding of these processes and to apply this information to studies that focus on the behavior and hazards of individual volcanoes.  The research involved identifying the areas of highest interest, planning the field investigations, determining the most appropriate sampling protocol, analyzing for the bulk composition and isotopic characteristics of the gas, and interpreting and publishing the results.