Publication Date:
2021-06-25
Description:
We show the results of a study on the volatiles dissolved inmineral waters discharged over a 200 km-long transect along the Rodna-Bârgău area and Călimani-Gurghiu-Harghita volcanic chain (Eastern Carpathians,
Romania). All of the collected mineral water samples carry dissolved gas with carbon dioxide content up to
1.99 cm3STP/gH2O, and heliumcontent up to 2.3 × 10−5 cm3STP/gH2O. Carbon (δ13CTDIC total dissolved inorganic
carbon, ranging from−15.6 to 5.32‰vs. VPDB), He systematics (He isotopes in the range of 0.38–0.99 Ra, Ra=air-normalized 3He/4He ratio) and CO2/3He ratio spanning over four orders ofmagnitude fromMORB-like values of 2.92× 109 to crustal-type values of 3.02 × 1013, coherently indicate the presence of fluids fromdifferent crustal sources (e.g. sediments, hydrocarbon reservoirs) besidesminor, but detectable contributions ofmantle/magmatic-derived fluids (up to 16.45%). Our investigations show that the wide range of chemical and isotopic composition can be explained in terms of mixings among different gas sources feeding the groundwater and the contemporary occurrence of gas-water interactions like degassing and deposition of carbonates, affecting the circulating waters after their infiltration.
Description:
Published
Description:
117-128
Description:
6A. Geochimica per l'ambiente
Description:
JCR Journal
Keywords:
Eastern Carpathians
;
Dissolved gases
;
Gas-water interactions
;
Helium 13CTDIC
;
gas geochemistry
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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