Using environmental tracers and numerical simulation to investigate regional hydrothermal basins - Norris Geyser Basin area, Yellowstone National Park, USA

Heat and fluid flow fields are simulated for several conceptual permeability fields and compared to processes inferred from environmental tracers in springs around Norris Geyser Basin, Yellowstone National Park. Large hydrothermal basins require specific permeability distributions in the upper crust. High permeability connections must exist between the land surface and high-temperature environments at depths of up to 5 km. The highest modeled temperatures are produced with a vertical conduit permeability of 10 ^-15m². Permeability at depths of 3-5 km must be within one order of magnitude of the near-surface permeability and must be ≥10 ^-16m². Environmental tracers from springs are used to develop a plausible numerical model of the local to regional groundwater flow field for the Norris Geyser Basin area. The model simulations provide insight into the dynamics of heat and fluid flow in a large regional hydrothermal system.