Chemical and isotopic composition of CO2-rich magnesium- sodium-bicarbonate-sulphate-type mineral waters from volcanoclastic aquifer in Rogaška Slatina, Slovenia

Nina Rman (Author), László Palcsu (Author), Andrej Lapanje (Author), Teodóra Szőcs (Author)

Abstract

Bottled natural mineral waters from an andesitic aquifer in Slovenia are enriched in magnesium (1.1 g/l), sulphate (2.2 g/l) and dissolved inorganic carbon (204 g/l). We analysed major ions, trace elements, tritium activity, 14 C, d18 OH2O , d2 HH2O, d13 CDIC, gas composition and noble gases in six wells. In addition, 87 Sr/ /86 Sr, d34 SSO4 and d11 B were analysed here for the first time. Stable isotopes with d18 O = -11.97 to -10.30% and d2 H = -77.3 to -63.8 confirm meteoric origin. CO2 degassing is evident at three wells, causing the oxygen shift of about -1.3%. Tritium activity was detectable only in the shallowest well, where the freshwater component was dated to the 1960s. d13 CDIC in five waters is -1.78 to ? 1.33%, typical of carbonate dissolution. Radiocarbon is low, 1.03–5.16 pMC. Chemical correction with bicarbonate concentration and d13 C correction methods gave best mean residence times, slightly longer than previously published. Sulphate has d34 S 26.6–28.9% and d18 O 8.9–11.1% due to dissolution of evaporites in carbonate rocks. Boron at concentrations of 1.2–6.1 mg/l has two origins: d11 B = 11.3–16.4% from hydrothermal alteration and d11 B = 26.6–31.7% from carbonate dissolution. Strontium at concentrations of 0.5–22.0 mg/l has 87 Sr/ /86 Sr, indicating three sources: 0.7106 for Miocene clastic rocks, 0.7082 for Triassic carbonates and 0.7070 for Lower Oligocene andesitic rocks. CO 2 represents the majority of the dissolved ([ 98.84 vol%) and separated gas ([ 95.23 vol%). Methane is only found in two wells with a max. of 0.30 vol%. All waters show excess helium and 16–97% of mantlederived helium. Since all show subsurface degassing, the paleo-infiltration temperature could not be calculated.

Keywords

hidrogeokemija;mineralna voda;naravna sledila;

Data

Language:	English
Year of publishing:	2022
Typology:	1.01 - Original Scientific Article
Organization:	GeoZS - Geological Survey of Slovenia
Publisher:	Springer Nature
UDC:	556.3
COBISS:	78400003
ISSN:	0269-4042
Views:	229
Downloads:	115
Average score:	0 (0 votes)
Metadata:

Other data

Type (COBISS):	Not categorized
Pages:	str. 2187–2214
Issue:	ǂvol. ǂ44
Chronology:	2022
DOI:	10.1007/s10653-021-01062-2
ID:	14834993