Publication Date:
2022-05-04
Description:
Springwater chemistry and carbon cycling in our study mainly depend on geological composition of the aquifer.
The investigated Alpine springs in Slovenia represent waters strongly influenced by chemicalweathering ofMesozoic
limestone and dolomite, only one spring was located in Permo-Carboniferous shales. The carbon isotopic
composition of dissolved inorganic carbon (DIC) and suspended organic carbon (POC) as well as major solute
concentrations yielded insights into the origin of carbon in Alpine spring waters. The major solute composition
was dominated by carbonic acid dissolution of calcite. Waters were generally close to saturation with respect
to calcite, and dissolved CO2 was up to fortyfold supersaturated relative to the atmosphere. δ13 C of DIC indicates
the portion of soil CO2 contributed in water and is related with soil thickness of infiltrating water in aquifer and
could be therefore used as a tool for vulnerability assessment. The δ13 C of DIC ranged from−15.8‰ to −1.5‰
and indicated less and more vulnerable aquifers. Mass balances of carbon for spring waters draining carbonate
rocks suggest that carbonate dissolution contributes from approximately 49% to 86% and degradation of organic
matter from 13.7% to 51.4%, depending on spring and its relation with rock type, soil environment, and geomorphic
position. Stable oxygen isotope composition of water (δ18OH2O), and tritium values range from −12.2 to
−9.3‰and from6.4 to 9.8 TU, respectively and indicate recharge frommodern precipitation. According to active
decay of tritiumand tritiumin modern precipitation the age of spring waters are estimated to be about 2.6 years
for springs located in Julian Alps, about 5 years for springs located in Karavanke and about 5 years for springs located
in Kamniško–Savinjske Alps.
Description:
Published
Description:
40-54
Description:
4.5. Studi sul degassamento naturale e sui gas petroliferi
Description:
JCR Journal
Description:
restricted
Keywords:
Hydrogeochemistry
;
Stable isotopes
;
Carbon
;
Oxygen
;
03. Hydrosphere::03.02. Hydrology::03.02.03. Groundwater processes
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
