Szczegóły publikacji

Autorzy (8)

• Dobrzyński Dariusz R.
• AGHDuliński Marek
• Karasiński Jakub
• Tetfejer Klaudia
• Tupys Andrii
• Stępień Marcin
• AGHWątor Katarzyna
• AGHRajchel Lucyna

Słowa kluczowe

Dane bibliometryczne

ID BaDAP	170005
Data dodania do BaDAP	2026-10-09
Tekst źródłowy	URL
DOI	10.1016/j.apgeochem.2026.107039
Rok publikacji	2026
Typ publikacji	artykuł w czasopiśmie
Otwarty dostęp
Creative Commons
Czasopismo/seria	Applied Geochemistry

Abstract

The germanium (Ge) content and its isotope ratio (IR) in saline and brine groundwaters from the Polish Outer Carpathians and Carpathian Foredeep (southern Poland) have been investigated. The Ge IR of continental groundwater in such geological environments has not previously been studied. This study found a wide variation in Ge concentrations in the groundwaters, increasing in the order of the following chemical water types: Na-Cl brines (<0.5–2.6 μg/L), Na-Cl saline waters (<0.5–42 μg/L), and Na-HCO3 saline waters (1.1–104 μg/L). The variation in Ge concentration is due to the different formation histories of the current composition of each water, including the mixing of formation water with infiltration water. The germanium in the studied formation water is derived mainly from minerals and organic matter transformed during the diagenesis of rock formations. The mixing of formation water with infiltration water results in a lower Ge concentration. In the Na-HCO3 saline groundwater, elevated Ge concentrations are accompanied by isotopically heavier oxygen compositions (with δ18O values of up to 6.2‰) due to the presence of dehydration water, which is released during the transformation of clay minerals, mainly the illitisation of smectite. The Ge IR values, which span a wide range (δ74/70Ge from 0.97‰ to 5.21‰), exceed previously reported values for continental groundwaters (1.21‰–4.02‰; Siebert et al., 2006; Baronas et al., 2020; Dobrzyński et al., 2024) and show greater enrichment in isotopically heavy Ge than continental crustal rocks (average δ74/70Ge value of 0.58 ± 0.21‰). The enrichment of the studied waters in heavier Ge isotopes was plausibly caused by the preferential removal of light isotopes by iron oxyhydroxides and clay minerals. The Ge IR values of formation waters are changed by (1) possible mixing with infiltration water components and, in the case of the shallowest water intakes, (2) the preferential immobilization of light Ge isotopes by secondary Fe oxyhydroxides and clay minerals abundantly present in the near-surface zone.