Breckel, E. J.. UW-Milwaukee, breckeej@whitman.edu
, . J.. ,

 
COMPARISON OF PORE WATER IN HYDROTHERMALLY ACTIVE AND NON-HYDROTHERMALLY ACTIVE AREAS IN YELLOWSTONE LAKE
 
Pore water collected in Yellowstone Lake was studied to determine if and how hydrothermal vent water influences lake sediments. The Yellowstone Caldera divides the lake into two areas. Sediment cores collected within the caldera, in areas of known vent activity, were compared to cores collected outside the boundary, where sediments are not hydrothermally altered. Three regions within the caldera, Mary Bay, West Thumb, and Stevenson Island, were compared to the study differences between sediments in these vent areas. Findings show cores taken in Mary Bay and West Thumb are influenced by vents. High concentrations of chloride were present in their pore waters. May Bay sediment contained the highest concentrations of chloride, measuring 9.10 mM at 32 cm into the sediment. This core was likely taken directly over a vent water reservoir calculated to contain a chloride concentration of 16 mM. Chloride gradients in these sediments also indicate a flux of chloride out of the pore water. Pore water from Southeast Arm, located outside the caldera, and Stevenson Island show no flux and contain concentrations of chloride consistent with levels measured in the lake water at 160 ÁM. Pore water profiles from Stevenson and Southeast Arm show only typical diagensis patterns.
 
Day: Wednesday, Feb. 3
Time: Poster
Location: Sweeney Center
 
Code: SS54WE1548S