2005: Evolution of fluid chemistry during travertine formation

• Main Authors: Ø. Hammer, B. Jamtveit, L. G. Benning, D. K. Dysthe
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Key words; arctic hot springs; carbonate precipitation; fluid evolution; travertine; Arctic; Bockfjorden; Svalbard; Troll
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.590.1826; http://folk.uio.no/dagkd/Publications/Geofluids_05/hammer_geofluids_2005.pdf

Arctic hydrothermal springs at Bockfjorden, Svalbard, have isotope and trace element signatures indicative of deri-vation from glacial melt waters with minor contribution from seawater. Downstream gradients in water chemistry, isotopic composition and carbonate precipitation rates have been documented for the Troll spring and travertine terrace system. The main controls on the downstream evolution of these parameters are carbon dioxide degas-sing, calcite precipitation, evaporation and biological activity. The carbonate precipitation rates not only show an approximately parabolic dependence on the calcite supersaturation levels, but depend also on local hydrodynam-ics. Downstream loss of light isotopes of oxygen and hydrogen can be explained as an effect of evaporation, as estimated using chloride as a conservative marker. Biological activity affects nitrate and bromide concentrations and influences the morphology of calcite precipitates.