HR: 1340h
AN: V53B-1335    [Abstracts]
TI: Patterns of Stream Flow and Temperature at Tantalus Creek, Norris Geyser Basin, Yellowstone National Park (USA)
AU: * Clor, L E
EM: Laura_Clor@nps.gov
AF: U.S. Geological Survey, VHZ, MS 910 345 Middlefield Road, Menlo Park, CA 94025, United States
AU: Lowenstern, J B
EM: jlwnstrn@usgs.gov
AF: U.S. Geological Survey, VHZ, MS 910 345 Middlefield Road, Menlo Park, CA 94025, United States
AU: Heasler, H P
EM: Henry_Heasler@nps.gov
AF: Yellowstone National Park, P.O. Box 168, Mammoth, WY 82190, United States
AB: We analyzed data for stream flow and water temperature from Tantalus Creek in the Norris Geyser Basin and their relationship to air temperature, precipitation and geyser eruptions during calendar year 2005. The creek is of special interest because ~97% of its waters are derived directly from outflow of Norris Geyser Basin hot springs. Understanding and tracking observed patterns and background behavior would improve our ability to reliably detect transient episodes of anomalous hydrothermal flow at Norris. From our analysis of the data, two separate diurnal patterns emerge: 1) in winter, water temperature and stream flow closely track those of air temperature; that is, water discharge and temperature increase during the day, and decrease at night. 2) in summer, water and air temperature are closely aligned but stream flow declines as soon as water temperature reaches its daily maximum. The winter pattern is present when the average daily temperature consistently drops below 0°C whereas the summer pattern is recognizable when the average daily temperature regularly exceeds 0°C. Spring and fall systematics are much more irregular, though both summer and winter patterns can be discerned occasionally during those seasons. We interpret increases in stream flow associated with the winter pattern to result from addition of water from melted snow and ice that increases in volume once air temperature increases in the morning. Melting is facilitated by the warm ground temperatures in the geyser basin, which are significantly higher than air temperatures in the winter. The summer pattern, however, appears to be strongly affected by increased evaporation in the afternoon, which decreases flow and buffers the temperature increase. In summary, the temperature of the air and the temperature difference between air and creek water appears to drive two distinct, seasonal hydrologic patterns. Finally, we note that discharge from eruptions at Echinus Geyser are clearly visible as peaks in the hydrograph, indicating that water from this geyser reaches the weir in 80 to 90 minutes, reflecting a slug of ~33,000 liters that travels about 0.4 meters per second.
DE: 1848 Monitoring networks
DE: 8419 Volcano monitoring (7280)
DE: 8424 Hydrothermal systems (0450, 1034, 3017, 3616, 4832, 8135)
SC: Volcanology, Geochemistry, Petrology [V]
MN: 2007 Fall Meeting