Date of Award
Master of Science in Geology (MS)
College, School or Department Name
Department of Geological and Mining Engineering and Sciences
Chad D. Deering
At Crater Hills, a thermally-altered area adjoining the Sour Creek resurgent dome that is located within the Yellowstone Caldera, we characterized volatile emissions based upon our soil degassing measurements and soil gas chemistry in 2014 and fumarole gas chemistry in 2007 (Bergfeld et al., 2011). The investigation at Crater Hills on its diffuse gases isotopes and CO2, H2S emission improve our understanding on its gas emission mode – including total emission and spatial distribution, and contribute to a more accurate estimation of total CO2 emission at Yellowstone volcanic system. The total emission of CO2 interpolated by sequential Gaussian simulation method (sGs) was 66 to 109 t d-1 with 95% confidence, which is an underestimation due to the inability to measure a high flux area on a slope as well as the absence of fumarole and pool emissions. Indicated by gas chemistry data of the fumarole at Crater Hills in 2007, the proportion of CO2 derived from magma would be at least 38% if considering the worst and unreasonable scenario; other scenarios give a much higher proportion of magma component, which would be over 50%. Faults or fractures covered by overlying alluvium are very likely to exist at Crater Hills, based on the similarity between the connection of high flux areas and the trend of the regional faults. The estimated emission of H2S was 0.39 t d-1, based on the linear correlation between H2S and CO2. The heat output was also estimated to be ~35MW with average heat flux of ~100 W m-2 based upon CO2-H2O-heat relations. The temperature of liquid-dominated reservoir was estimated to be 270-300 ⁰C estimated by Fournier (1989), and was 213 ⁰C to 217 ⁰C for the vapor-dominated reservoir which is the source for the sampled fumarole gas in 2007.
Lin, Peipei, "ORIGIN AND QUANTIFICATION OF DIFFUSE CO2 AND H2S EMISSION AT CRATER HILLS, YELLOWSTONE NATIONAL PARK", Master's Thesis, Michigan Technological University, 2015.