Open AccessThe Systematics of Chlorine, Lithium, and Boron and δ 37 Cl, δ 7 Li, and δ 11 B in the Hydrothermal System of the Yellowstone Plateau Volcanic Field
Author(s) -
Cullen Jeffrey T.,
Hurwitz Shaul,
Barnes Jaime D.,
Lassiter John C.,
PennistonDorland Sarah,
Meixner Anette,
Wilckens Frederike,
Kasemann Simone A.,
McCleskey R. Blaine
Publication year - 2021
Publication title -
geochemistry, geophysics, geosystems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.928
H-Index - 136
ISSN - 1525-2027
DOI - 10.1029/2020gc009589
Subject(s) - rhyolite , boron , chlorine , geology , hydrothermal circulation , chloride , mineralogy , geochemistry , volcanic rock , chemistry , volcano , organic chemistry , seismology
Chlorine, lithium, and boron are trace elements in rhyolite but are enriched in groundwater flowing through rhyolite because they tend to partition into the fluid phase during high‐temperature fluid‐rock reactions. We present a large data set of major element and δ 37 Cl, δ 7 Li, and δ 11 B compositions of thermal water and rhyolite from Yellowstone Plateau Volcanic Field (YPVF). The Cl/B, Cl/Li, δ 37 Cl (−0.2‰ to +0.7‰), and δ 11 B (−6.2‰ to −5.9‰) values of alkaline‐chloride thermal waters reflect high‐temperature leaching of chlorine, lithium, and boron from rhyolite that has δ 37 Cl and δ 11 B values of +0.1‰ to +0.9‰ and −6.3‰ to −6.2‰, respectively. Chlorine and boron are not reactive, but lithium incorporation into hydrothermal alteration minerals results in a large range of Cl/Li, B/Li, and δ 7 Li (−1.2‰ to +3.8‰) values in thermal waters. The relatively large range in δ 7 Li values of thermal waters reflects a large range of values in rhyolite. Large volumes of rhyolite must be leached to account for the chloride, lithium and boron fluxes, implying deep groundwater flow through rhyolite flows and tuffs representing Yellowstone's three eruptive cycles (∼2.1 Ma). Lower Cl/B values in acid‐sulfate waters result from preferential partitioning of boron into the vapor phase and enrichment in the near‐surface water condensate. The Cl/B, Cl/Li, δ 7 Li (−0.3‰ to +2.1‰), and δ 11 B (−8.0‰ to −8.1‰) values of travertine depositing calcium‐carbonate thermal waters which discharge in the northern and southern YPVF suggest that chlorine, lithium, and boron are derived from Mesozoic siliciclastic sediments which contain detrital material from the underlying metamorphic basement.