Andrew G Hunt
Andy Hunt is a Research Geologist with the Geology, Geophysics, and Geochemistry Science Center.
Science and Products
Filter Total Items: 61
Geochemistry and fluxes of gases from hydrothermal features at Newberry Volcano, Oregon, USA
We present the chemical and isotopic compositions of gases and fluxes of CO2 from the hydrothermal features of Newberry Volcano, a large composite volcano located in Oregon's Cascade Range with a summit caldera that hosts two lakes, Paulina and East Lakes. Gas samples were collected from 1982 to 2021 from Paulina Hot Springs (PHS) on the shore of Paulina Lake, East Lake Hot Springs (ELHS...
Authors
Jennifer L. Lewicki, William C. Evans, Steven E. Ingebritsen, Laura Clor, Peter J. Kelly, Sara E. Peek, Robert A. Jensen, Andrew G. Hunt
Improving gas-derived parameterization of groundwater using free phase gas measurements
Dissolved atmogenic gasses in groundwater provide significant information about recharge conditions, flowpath, and age. Free phase gas in aquifers is largely ignored in these analyses and there is a lack of quantitative analysis for gas flux mechanisms. Many related fields encountering multiphase flow acknowledge that the presence of bubbles allows for the rapid exsolution of dissolved...
Authors
Robert J Agnew, Andrew G. Hunt, Todd Halihan
Over a third of groundwater in USA public-supply aquifers is Anthropocene-age and susceptible to surface contamination
The distribution of groundwater age is useful for evaluating the susceptibility and sustainability of groundwater resources. Here, we compute the aquifer-scale cumulative distribution function to characterize the age distribution for 21 Principal Aquifers that account for ~80% of public-supply pumping in the United States. The aquifer-scale cumulative distribution function for each...
Authors
Bryant Jurgens, Kirsten Faulkner, Peter B. McMahon, Andrew G. Hunt, Gerolamo C. Casile, Megan B. Young, Kenneth Belitz
Occurrence of water and thermogenic gas from oil-bearing formations in groundwater near the Orcutt Oil Field, California, USA
Study regionSanta Barbara County, California, USA.Study focusTo analyze a wide array of newly collected chemical, isotopic, dissolved gas, and age dating tracers in conjunction with historical data from groundwater and oil wells to determine if water and/or thermogenic gas from oil-bearing formations have mixed with groundwater in the Orcutt Oil Field and surrounding area.New...
Authors
Robert Anders, Matthew K. Landon, Peter B. McMahon, Justin T. Kulongoski, Andrew G. Hunt, Tracy Davis
Noble gas signatures constrain oil-field water as the carrier phase of hydrocarbons occurring in shallow aquifers in the San Joaquin Basin, USA
Noble gases record fluid interactions in multiphase subsurface environments through fractionation processes during fluid equilibration. Water in the presence of hydrocarbons at the subsurface acquires a distinct elemental signature due to the difference in solubility between these two fluids. We find the atmospheric noble gas signature in produced water is partially preserved after...
Authors
Ruta Karolyte, Peter H. Barry, Andrew G. Hunt, Justin T. Kulongoski, R. L. Tyne, Tracy Davis, Michael Wright, Peter B. McMahon, C. J. Ballentine
Relative risk of groundwater-quality degradation near California (USA) oil fields estimated from 3H, 14C, and 4He
Relative risks of groundwater-quality degradation near selected California oil fields are estimated by examining spatial and temporal patterns in chemical and isotopic data in the context of groundwater-age categories defined by tritium and carbon-14. In the Coastal basins, western San Joaquin Valley (SJV), and eastern SJV; 82, 76, and 0% of samples are premodern (pre-1953 recharge)...
Authors
Peter B. McMahon, Matthew K. Landon, Tracy Davis, Michael Wright, Celia Zamora, Robert Anders, Michael Land, Justin T. Kulongoski, Andrew G. Hunt
Chemical and isotopic data on gases and waters for thermal and non-thermal features across Yellowstone National Park (2003-2015)
Degassing thermal features at Yellowstone National Park include spectacular geysers, roiling hot springs, bubbling mud pots, fumaroles, frying pans, and areas of passive degassing characterized by steaming ground. Most of these features are readily identified by visible clouds of steam that are occasionally accompanied by a strong rotten egg odor from emissions of hydrogen sulfide gas...
Fumarole gas geochemistry and tree-ring radiocarbon data at Mammoth Mountain, California (1989-2016)
Mammoth Mountain is a dacitic dome complex located on the southwestern rim of Long Valley Caldera, California. Mammoth Mountain has exhibited unrest over the past ~30 years, characterized by seismicity over a broad range of depths, elevated 3He/4He ratios in fumarolic gas and large-scale diffuse CO2 emissions. Monitoring of this unrest has included collection of fumarole gas samples for...
Science and Products
Filter Total Items: 61
Geochemistry and fluxes of gases from hydrothermal features at Newberry Volcano, Oregon, USA
We present the chemical and isotopic compositions of gases and fluxes of CO2 from the hydrothermal features of Newberry Volcano, a large composite volcano located in Oregon's Cascade Range with a summit caldera that hosts two lakes, Paulina and East Lakes. Gas samples were collected from 1982 to 2021 from Paulina Hot Springs (PHS) on the shore of Paulina Lake, East Lake Hot Springs (ELHS...
Authors
Jennifer L. Lewicki, William C. Evans, Steven E. Ingebritsen, Laura Clor, Peter J. Kelly, Sara E. Peek, Robert A. Jensen, Andrew G. Hunt
Improving gas-derived parameterization of groundwater using free phase gas measurements
Dissolved atmogenic gasses in groundwater provide significant information about recharge conditions, flowpath, and age. Free phase gas in aquifers is largely ignored in these analyses and there is a lack of quantitative analysis for gas flux mechanisms. Many related fields encountering multiphase flow acknowledge that the presence of bubbles allows for the rapid exsolution of dissolved...
Authors
Robert J Agnew, Andrew G. Hunt, Todd Halihan
Over a third of groundwater in USA public-supply aquifers is Anthropocene-age and susceptible to surface contamination
The distribution of groundwater age is useful for evaluating the susceptibility and sustainability of groundwater resources. Here, we compute the aquifer-scale cumulative distribution function to characterize the age distribution for 21 Principal Aquifers that account for ~80% of public-supply pumping in the United States. The aquifer-scale cumulative distribution function for each...
Authors
Bryant Jurgens, Kirsten Faulkner, Peter B. McMahon, Andrew G. Hunt, Gerolamo C. Casile, Megan B. Young, Kenneth Belitz
Occurrence of water and thermogenic gas from oil-bearing formations in groundwater near the Orcutt Oil Field, California, USA
Study regionSanta Barbara County, California, USA.Study focusTo analyze a wide array of newly collected chemical, isotopic, dissolved gas, and age dating tracers in conjunction with historical data from groundwater and oil wells to determine if water and/or thermogenic gas from oil-bearing formations have mixed with groundwater in the Orcutt Oil Field and surrounding area.New...
Authors
Robert Anders, Matthew K. Landon, Peter B. McMahon, Justin T. Kulongoski, Andrew G. Hunt, Tracy Davis
Noble gas signatures constrain oil-field water as the carrier phase of hydrocarbons occurring in shallow aquifers in the San Joaquin Basin, USA
Noble gases record fluid interactions in multiphase subsurface environments through fractionation processes during fluid equilibration. Water in the presence of hydrocarbons at the subsurface acquires a distinct elemental signature due to the difference in solubility between these two fluids. We find the atmospheric noble gas signature in produced water is partially preserved after...
Authors
Ruta Karolyte, Peter H. Barry, Andrew G. Hunt, Justin T. Kulongoski, R. L. Tyne, Tracy Davis, Michael Wright, Peter B. McMahon, C. J. Ballentine
Relative risk of groundwater-quality degradation near California (USA) oil fields estimated from 3H, 14C, and 4He
Relative risks of groundwater-quality degradation near selected California oil fields are estimated by examining spatial and temporal patterns in chemical and isotopic data in the context of groundwater-age categories defined by tritium and carbon-14. In the Coastal basins, western San Joaquin Valley (SJV), and eastern SJV; 82, 76, and 0% of samples are premodern (pre-1953 recharge)...
Authors
Peter B. McMahon, Matthew K. Landon, Tracy Davis, Michael Wright, Celia Zamora, Robert Anders, Michael Land, Justin T. Kulongoski, Andrew G. Hunt
Chemical and isotopic data on gases and waters for thermal and non-thermal features across Yellowstone National Park (2003-2015)
Degassing thermal features at Yellowstone National Park include spectacular geysers, roiling hot springs, bubbling mud pots, fumaroles, frying pans, and areas of passive degassing characterized by steaming ground. Most of these features are readily identified by visible clouds of steam that are occasionally accompanied by a strong rotten egg odor from emissions of hydrogen sulfide gas...
Fumarole gas geochemistry and tree-ring radiocarbon data at Mammoth Mountain, California (1989-2016)
Mammoth Mountain is a dacitic dome complex located on the southwestern rim of Long Valley Caldera, California. Mammoth Mountain has exhibited unrest over the past ~30 years, characterized by seismicity over a broad range of depths, elevated 3He/4He ratios in fumarolic gas and large-scale diffuse CO2 emissions. Monitoring of this unrest has included collection of fumarole gas samples for...