Suche nach Personen

plus im Publikationsserver
plus bei Google Scholar

Bibliografische Daten exportieren
 

Electrical conductivity of HCl-bearing aqueous fluids to 700 ºC and 1 GPa

DOI zum Zitieren der Version auf EPub Bayreuth: https://doi.org/10.15495/EPub_UBT_00005341
URN zum Zitieren der Version auf EPub Bayreuth: urn:nbn:de:bvb:703-epub-5341-1

Titelangaben

Klumbach, Steffen ; Keppler, Hans:
Electrical conductivity of HCl-bearing aqueous fluids to 700 ºC and 1 GPa.
In: Contributions to Mineralogy and Petrology. Bd. 175 (2020) Heft 12 . - No. 114.
ISSN 1432-0967
DOI der Verlagsversion: https://doi.org/10.1007/s00410-020-01754-5

Volltext

[thumbnail of Klumbach-Keppler2020_Article_ElectricalConductivityOfHCl-be.pdf]
Format: PDF
Name: Klumbach-Keppler2020_Article_ElectricalConductivityOfHCl-be.pdf
Version: Veröffentlichte Version
Verfügbar mit der Lizenz Creative Commons BY 4.0: Namensnennung
Download (3MB)

Abstract

Subsurface magmatic–hydrothermal systems are often associated with elevated electrical conductivities in the Earthʼs crust. To facilitate the interpretation of these data and to allow distinguishing between the effects of silicate melts and fluids, the electrical conductivity of aqueous fluids in the system H2O–HCl was measured in an externally heated diamond anvil cell. Data were collected to 700 °C and 1 GPa, for HCl concentrations equivalent to 0.01, 0.1, and 1 mol/l at ambient conditions. The data, therefore, more than double the pressure range of previous measurements and extend them to geologically realistic HCl concentrations. The conductivities $$\sigma$$(in S/m) are well reproduced by a numerical model log $$\sigma$$ = −2.032 + 205.8 T−1 + 0.895 log c + 3.888 log $$\rho$$ + log$$\Lambda_{0}$$(T,$$\rho$$), where T is the temperature in K, c is the HCl concentration in wt. %, and $$\rho$$is the density of pure water at the corresponding pressure and temperature conditions. $$\Lambda_{0}$$(T,$$\rho$$) is the limiting molar conductivity (in S cm2 mol−1) at infinite dilution, $$\Lambda_{0}$$(T,$$\rho$$) = 2550.14 − 505.10$$\rho$$ − 429,437 T−1. A regression fit of more than 800 data points to this model yielded R2 = 0.95. Conductivities increase with pressure and fluid densities due to an enhanced dissociation of HCl. However, at constant pressures, conductivities decrease with temperature because of reduced dissociation. This effect is particularly strong at shallow crustal pressures of 100–200 MPa and can reduce conductivities by two orders of magnitude. We, therefore, suggest that the low conductivities sometimes observed at shallow depths below the volcanic centers in magmatic–hydrothermal systems may simply reflect elevated temperatures. The strong negative temperature effect on fluid conductivities may offer a possibility for the remote sensing of temperature variations in such systems and may allow distinguishing the effects of magma intrusions from changes in hydrothermal circulation. The generally very high conductivities of HCl–NaCl–H2O fluids at deep crustal pressures (500 MPa–1 GPa) imply that electrical conductors in the deep crust, as in the Altiplano magmatic province and elsewhere, may at least partially be due to hydrothermal activity.

Weitere Angaben

Publikationsform: Artikel in einer Zeitschrift
Keywords: electrical conductivity; fluid; HCl; hydrothermal systems; magnetotelluric data
Themengebiete aus DDC: 500 Naturwissenschaften und Mathematik > 550 Geowissenschaften, Geologie
Institutionen der Universität: Forschungseinrichtungen > Zentrale wissenschaftliche Einrichtungen > Bayerisches Forschungsinstitut für Experimentelle Geochemie und Geophysik - BGI
Forschungseinrichtungen
Forschungseinrichtungen > Zentrale wissenschaftliche Einrichtungen
Sprache: Englisch
Titel an der UBT entstanden: Ja
URN: urn:nbn:de:bvb:703-epub-5341-1
Eingestellt am: 18 Mrz 2021 11:19
Letzte Änderung: 23 Nov 2023 11:17
URI: https://epub.uni-bayreuth.de/id/eprint/5341

Downloads

Downloads pro Monat im letzten Jahr