Sulfur geochemistry of hydrothermal waters in Yellowstone National Park. 1: The origin of thiosulfate in hot spring waters

Journal Article · Tue Dec 01 04:00:00 EST 1998 · Geochimica et Cosmochimica Acta

DOI:https://doi.org/10.1016/S0016-7037(98)00269-5· OSTI ID:343753

Xu, Y; Schoonen, M A.A. ^[1]; Nordstrom, D K; Cunningham, K M; Ball, J W ^[2]

---

1. SUNY, Stony Brook, NY (United States). Dept. of Geosciences
2. Geological Survey, Boulder, CO (United States). Water Resources Div.

Thiosulfate (S{sub 2}O{sub 3}{sup 2{minus}}), polythionate (S{sub x}O{sub 6}{sup 2{minus}}), dissolved sulfide (H{sub 2}S), and sulfate (SO{sub 4}{sup 2{minus}}) concentrations in thirty-nine alkaline and acidic springs in Yellowstone National Park (YNP) were determined. The analyses were conducted on site, using ion chromatography for thiosulfate, polythionate, and sulfate, and using colorimetry for dissolved sulfide. Thiosulfate was detected at concentrations typically less than 2 {micro}mol/L in neutral and alkaline chloride springs with low sulfate concentrations (Cl{sup {minus}}/SO{sub 4}{sup 2{minus}} > 25). The thiosulfate concentration levels are about one to two orders of magnitude lower than the concentration of dissolved sulfide in these springs. In most acid sulfate and acid sulfate-chloride springs (Cl{sup {minus}}/SO{sub 4}{sup 2{minus}} < 10), thiosulfate concentrations were also typically lower than 2 {micro}mol/L. However, in some chloride springs enriched with sulfate (Cl{sup {minus}}/SO{sub 4}{sup 2{minus}} between 10 and 25), thiosulfate was found at concentrations ranging from 9 to 95 {micro}mol/L, higher than the concentrations of dissolved sulfide in these waters. Polythionate was detected only in Cinder Pool, Norris Geyser basin, at concentrations up to 8 {micro}mol/L, with an average S-chain-length from 4.1 to 4.9 sulfur atoms. The results indicate that no thiosulfate occurs in the deeper parts of the hydrothermal system. Thiosulfate may form, however, from (1) hydrolysis of native sulfur by hydrothermal solutions in the shallower parts (<50 m) of the system, (2) oxidation of dissolved sulfide upon mixing of a deep hydrothermal water with aerated shallow groundwater, and (3) the oxidation of dissolved sulfide by dissolved oxygen upon discharge of the hot spring. Upon discharge of a sulfide-containing hydrothermal water, oxidation proceeds rapidly as atmospheric oxygen enters the water. The transfer of oxygen is particularly effective if the hydrothermal discharge is turbulent and has a large surface area.

• OSTI ID: 343753
• Journal Information: Geochimica et Cosmochimica Acta, Journal Name: Geochimica et Cosmochimica Acta Journal Issue: 23-34 Vol. 62; ISSN GCACAK; ISSN 0016-7037
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
COMPILED DATA
GEOCHEMISTRY
GEOTHERMAL FLUIDS
HOT SPRINGS
HYDROLYSIS
ORIGIN
OXIDATION
THIOSULFATES
WATER CHEMISTRY
YELLOWSTONE NATIONAL PARK