Mineralogical and geochemical significance of secondary burial-related barite and celestine : evidence from Late Paleozoic evaporites in the Karawanke Mountains (Slovenia)

Šoster, Aleš (avtor), Dolenec, Matej (avtor), Grum Verdinek, Luna (avtor), Zavašnik, Janez (avtor)

The evaporites in the Karawanke Mountains (northwestern Slovenia) are hosted in a structurally complex lithological sequence, intercalated between Carboniferous-Permian and Permo-Triassic rocks. These evaporites are primarily composed of gypsum, with minor amounts of anhydrite, dolomite, and barite-celestine. Geochemically, the evaporites are characterized by elevated Sr (2000–2700 mg kg$^{−1}$) and low Ba (210–400 mg kg$^{−1}$) contents, reflecting the contrasting solubility behaviors of these elements in low-temperature syngenetic environments. Thermal dehydration, induced by peak burial temperatures ranging from 190 to 260 °C facilitated the transformation of gypsum to anhydrite. Subsequent cooling below the anhydrite stability threshold enabled gradual rehydration, accounting for the coexistence of both minerals. Thermal alteration also mobilized trace elements from the evaporites, which precipitated as secondary celestine and barite through dissolution-reprecipitation mechanisms, producing compositionally zoned fracture infills. The observed zoning, transitioning from Ba-rich to Sr-rich endmembers, likely reflects shifts in temperature, solubility and the chemical reactivity of evaporite-derived brine. Sulfur isotope analyses reveal δ$^{34}$S values of +11.8 to +13.7 ‰ for the evaporitic sulfates, showing minimal variation and only a small difference relative to coexisting sulfides. This small isotopic offset indicates nearly complete sulfate reduction under high-temperature conditions, consistent with thermal alteration inferred from burial temperatures. These geochemical and isotopic results put forward not only the thermal and diagenetic evolution of the Karawanke evaporites but also their broader significance as minor reservoirs of strontium, a critical element with growing industrial and technological importance.

• Jezik: Angleški jezik
• Ključne besede: evaporites, gypsum, barite, celestine, geochemistry, critical elements
• Vrsta gradiva: Članek v reviji
• Tipologija: 1.01 - Izvirni znanstveni članek
• Organizacija: NTF - Naravoslovnotehniška fakulteta
• Status publikacije: Objavljeno
• Različica publikacije: Objavljena publikacija
• Leto izida: 2025
• Št. strani: 12 str.
• Številčenje: Vol. 85, iss. 4, art. 126354
• PID: 20.500.12556/RUL-182779
• UDK: 55
• ISSN pri članku: 0009-2819
• DOI: 10.1016/j.chemer.2025.126354
• COBISS.SI-ID: 258757379
• Datum objave v RUL: 22.05.2026

Gradivo je del revije

• Naslov: Chemie der Erde
• Skrajšan naslov: Chem. Erde
• Založnik: Gustav Fischer Verlag
• ISSN: 0009-2819
• COBISS.SI-ID: 25211136

Licence

• Licenca: CC BY 4.0, Creative Commons Priznanje avtorstva 4.0 Mednarodna
• Povezava: http://creativecommons.org/licenses/by/4.0/deed.sl
• Opis: To je standardna licenca Creative Commons, ki daje uporabnikom največ možnosti za nadaljnjo uporabo dela, pri čemer morajo navesti avtorja.

Projekti

• Financer: ARRS - Agencija za raziskovalno dejavnost Republike Slovenije
• Številka projekta: P1-0195
• Naslov: Geookolje in geomateriali

• Financer: ARIS - Javna agencija za znanstvenoraziskovalno in inovacijsko dejavnost Republike Slovenije
• Številka projekta: N1-0164
• Naslov: Geobiokemijski cikel molibdena v kamninah in sedimentih