Please use this identifier to cite or link to this item: http://hdl.handle.net/2122/8312
AuthorsChiodini, G.* 
Caliro, S.* 
Lowenstern, J. B.* 
Evans, W. C.* 
Bergfeld, D.* 
Tassi, F.* 
Tedesco, D.* 
TitleInsights from fumarole gas geochemistry on the origin of hydrothermal fluids on the Yellowstone Plateau
Issue Date2012
Series/Report no./89 (2012)
DOI10.1016/j.gca.2012.04.051
URIhttp://hdl.handle.net/2122/8312
Keywordshydrothermal fluids
Yellowstone Plateau
Subject Classification04. Solid Earth::04.03. Geodesy::04.03.06. Measurements and monitoring 
04. Solid Earth::04.04. Geology::04.04.12. Fluid Geochemistry 
04. Solid Earth::04.08. Volcanology::04.08.01. Gases 
AbstractThe chemistry of Yellowstone fumarole gases shows the existence of two component waters, type MC, influenced by the addition of deep mantle fluid, and type CC, influenced by crustal interactions (CC). MC is high in 3He/4He (22 Ra) and low in 4He/40Ar ( 1), reflecting input of deep mantle components. The other water is characterized by 4He concentrations 3–4 orders of magnitude higher than air-saturated meteoric water (ASW). These high He concentrations originate through circulation in Pleistocene volcanic rocks, as well as outgassing of Tertiary and older (including Archean) basement, some of which could be particularly rich in uranium, a major 4He source. Consideration of CO2–CH4–CO–H2O–H2 gas equilibrium reactions indicates equilibration temperatures from 170 C to 310 C. The estimated temperatures highly correlate with noble-gas variations, suggesting that the two waters differ in temperature. Type CC is 170 C whereas the MC is hotter, at 340 C. This result is similar to models proposed by previous studies of thermal water chemistry. However, instead of mixing the deep hot component simply with cold, meteoric waters we argue that addition of a 4He-rich component, equilibrated at temperatures around 170 C, is necessary to explain the range in fumarole gas chemistry.
Appears in Collections:Papers Published / Papers in press

Files in This Item:
File Description SizeFormat 
chiocal (2012).pdf1.07 MBAdobe PDFView/Open    Request a copy
Show full item record

Page view(s)

106
checked on Apr 22, 2017

Download(s)

24
checked on Apr 22, 2017

Google ScholarTM

Check

Altmetric