Aguilar, C. Univ. of Wisconsin--Milwaukee, aguilar@uwm.edu
Cuhel, R. Univ. of Wisconsin--Milwaukee, rcuhel@uwm.edu
Lovalvo, D. Eastern Oceanics,

 
PORE WATER, VENT WATER AND GROUND WATER INPUTS TO GEOTHERMALLY-ACTIVE YELLOWSTONE LAKE, WYOMING
 
Mineral inputs to Yellowstone Lake come from a variety of sources, namely hydrothermal vents, ground water, rain water, flux from sediments and direct runoff. Approximately one third of Yellowstone Lake is directly influenced by hydrothermal activity (hot water vents and fumaroles). In a lake-wide survey, groundwater was often enriched in silicate and sulfate relative to adjacent lake water. Surveys of lake- , vent- and sediment pore water gradients established zones of direct and subsurface inputs of geochemically altered fluids. Pore water and vent water chemistry provide evidence for lake water dilution of vents below the sediment-water interface. Significant fracturing of source water bedrock was indicated by extreme differences in pore water profiles from cores less than 5m apart in geothermally vigorous West Thumb. Some samples approached theoretical reservoir composition for conservative minerals. Fine scale samplers demonstrated strong gradients on the 10 to 30 cm scale. Redox labile species (H2S, FeII) varied substantially among vents and pore waters, but evidence for their persistence was apparent in the solid phase. Despite high variability among locations significant differences in geothermal contributions to lake chemistry were apparent in different basins. Caldera regions each contained characteristic signatures relative to non-influenced Southeast Arm controls.
 
Day: Wednesday, Feb. 3
Time: Poster
Location: Sweeney Center
 
Code: SS28WE1539S