Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1016/j.gca.2004.05.032
Title (Primary) Evidence for a nitrogen flux directly derived from the European subcontinental mantle in the Western Eger Rift, central Europe
Author Bräuer, K.; Kämpf, H.; Niedermann, S.; Strauch, G.; Weise, S.M.
Source Titel Geochimica et Cosmochimica Acta
Year 2004
Department HDG; ISOHYD
Volume 68
Issue 23
Page From 4935
Page To 4947
Language englisch
Abstract In the Czech-German border region of the Vogtland and NW Bohemia (western Eger rift, Central Europe), chemical and isotopic compositions (C, N, He, Ar) of free gas from a thermal water escape (fluorite mine, Schönbrunn), two mineral springs (“Eisenquelle,” Bad Brambach; “Sprudel III,” Bad Elster) and a mofette (Bublak) located along an ∼40-km long traverse are reported. The gases of Bublak and Bad Brambach are CO2-rich (>99 vol.%) and have δ13C values of −1.95 and −4.29‰, respectively. With distance from the center of CO2 degassing (Bublak) the δ13C values decrease, most likely due to physico-chemical fractionation of CO2 between gaseous and aqueous phases rather than to admixture of organic/biogenic CO2. The δ15N values range between −3.2 and −0.6‰, compared to an upper mantle value of −4.0 ± 1.0‰. The four locations are characterized by 3He/4He ratios decreasing from 5.9 Ra in the center (Bublak) to 0.8 Ra in the periphery (Schönbrunn) and give evidence for mixing of He from a deep-seated magmatic source with a crustal source. The location with the highest 3He/4He ratio (5.9 Ra) is accompanied by the highest 40Ar/36Ar (550). We argue that the nitrogen of the Bublak mofette gas is a mixture of predominantly atmospheric and mantle-derived components, whereas at the other three locations crustal nitrogen may also be present. The Bublak δ15N value of ≈−4.5 ± 1.0‰ represents the first free gas δ15N reference from the European subcontinental mantle (ESCM) and indicates that, in contrast to the 3He/4He ratios, the δ15N values are equal for ESCM and MORB, respectively.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=4010
Bräuer, K., Kämpf, H., Niedermann, S., Strauch, G., Weise, S.M. (2004):
Evidence for a nitrogen flux directly derived from the European subcontinental mantle in the Western Eger Rift, central Europe
Geochim. Cosmochim. Acta 68 (23), 4935 - 4947 10.1016/j.gca.2004.05.032