Trace and rare earth element distribution in hyperalkaline serpentinite-hosted spring waters and associated authigenic carbonates from the Ronda peridotite

Author(s)
Jennifer Zwicker, Daniel Smrzka, Inaki Vadillo, Pablo Jiminez, Manolis Giampouras, Jörn Peckmann, Wolfgang Bach
Abstract

The Ronda peridotite in southern Spain is subject to low-temperature serpentinization by circulating groundwaters that produces hyperalkaline fluids of high pH and low dissolved inorganic carbon content (DIC). When these waters resurface as hyperalkaline springs they take up atmospheric carbon dioxide (CO

2), which triggers the precipitation of travertine carbonates. Spring waters at Baños del Duque, Fuente Romana, and Fuente Amargosa show typical chemical features of hyperalkaline springs such as high pH and low DIC, yet exhibit an unusual distribution of rare earth elements (REEs) enriched in lanthanum (La) and cerium (Ce). In order to constrain changes in spring water chemistry and carbonate precipitation during atmospheric CO

2 uptake, a reaction path model was set up to illustrate that the distribution of REE species in the high pH and low DIC water is strongly dependent on REE complexation by hydroxide and carbonate species. Reaction path modeling results show that during spring fluid emission and CO

2 uptake, REE speciation in the fluids shifts from a dominance of hydroxide to carbonate complexes. The complexation of rare earth elements in the high pH, low DIC fluids strongly depends on the DIC content of the respective fluid. The REE distribution of travertine deposits associated with the hyperalkaline springs deviates from that in the fluids, suggesting that travertines precipitated from fluids different to those currently emitted from the springs.

Organisation(s)
Department of Mineralogy and Crystallography
External organisation(s)
Universidad de Málaga, Universidad de Granada, Universität Hamburg, Universität Bremen
Journal
Applied Geochemistry
Volume
147
No. of pages
17
ISSN
0883-2927
DOI
https://doi.org/10.1016/j.apgeochem.2022.105492
Publication date
12-2022
Peer reviewed
Yes
Austrian Fields of Science 2012
105105 Geochemistry
Keywords
ASJC Scopus subject areas
Pollution, Geochemistry and Petrology, Environmental Chemistry
Portal url
https://ucris.univie.ac.at/portal/en/publications/trace-and-rare-earth-element-distribution-in-hyperalkaline-serpentinitehosted-spring-waters-and-associated-authigenic-carbonates-from-the-ronda-peridotite(9ae8d836-6386-4606-a06a-77190108c8d7).html