Upper Triassic foraminifera from the Northern Calcareous Alps, Austria

Gale, Luka (author), Mette, Wolfgang (author)

Foraminiferal assemblages and proportions of foraminiferal morphogroups were determined from Upper Triassic deposits of the Eiberg Basin and the Hallstatt Zone of the Northern Calcareous Alps in Austria (Eastern Alps). Foraminifera were hand-picked from the residue of marl samples taken from the upper Norian Pötschenkalk Formation, the middle–upper Rhaetian Zlambach Formation, and the uppermost Rhaetian Tiefengraben Member of the Kendlbach Formation. In total, 72 species from 31 genera were determined. Foraminiferal assemblages from the Pötschenkalk Formation at the Thälerergraben section are relatively diverse.Dentalina, Ammodiscus, Nodosaria, and Glomospirella dominate. Foraminiferal assemblages from the Zlambach Formation at the Rossmoos-/Stambachgraben section are also abundant and diverse. The most common foraminifera are Reophax, Dentalina, and Annulina. The uppermost Kössen Formation at the Schlossgraben section is dominated by hyaline taxa. The most common genera are Ichthyolaria, Lenticulina, and Nodosaria. At the Fonsjoch section, the uppermost Kössen Formation contains Lenticulina, Astacolus, and Trochammina. An increase in opportunists suggests variations in oxygen levels during the deposition of the uppermost Kössen Formation. The Kendlbach Formation at the Schlossgraben section is dominated by Lagenida over agglutinated taxa. Astacolus, Lenticulina, and Trochammina are the most common genera. At the Fonsjoch section, the Kendlbach Formation contains mostly Ast acolus, followed by Trochammina, Ammobaculites, Reophax, and Lenticulina. Increases in opportunists point to increased stressful conditions. An increase in nodosariid foraminifera higher up the section indicates a return to better oxygenated conditions.

• Language: English
• Keywords: foraminifere, fosili, trias, zgornji, jura, zgornja, Pötschenkalk, Zlambach formacija, Kössen formacija, Kendlbach formacija, morfoskupina
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: NTF - Faculty of Natural Sciences and Engineering
• Publication status: Published
• Publication version: Version of Record
• Publication date: 22.06.2026
• Year: 2026
• Number of pages: str. 93-142
• Numbering: ǂvol. ǂ69, ǂno. ǂ1
• PID: 20.500.12556/RUL-184454
• UDC: 56
• ISSN on article: 0016-7789
• DOI: 10.5474/geologija.2026.005
• COBISS.SI-ID: 283533315
• Publication date in RUL: 08.07.2026

Record is a part of a journal

• Title: Geologija
• Shortened title: Geologija
• Publisher: Geološki zavod Slovenije
• ISSN: 0016-7789
• COBISS.SI-ID: 5636866

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Title: Zgornjetriasne foraminifere iz Severnih apneniških Alp, Avstrija

Abstract

V okviru pričujoče raziskave smo določili foraminiferne združbe in foraminiferne morfoskupine iz zgornjetriasnih in spodnje spodnjejurskih plasti bazena Eiberg in območja Hallstatt današnjih Severnih Apneniških Alp v Avstriji (Vzhodne Alpe). Foraminifere so bile ročno pobrane iz netopnega ostanka vzorcev laporja iz zgornjenorijske Pötschenkalk formacije, srednje–zgornjeretijske Zlambach formacije in zgornjeretijskega dela Tiefengraben člena Kendlbach formacije. Skupno je bilo določenih 72 vrst, ki pripadajo 31 rodovom. Foraminiferne združbe Pötschenkalk formacije v profilu Thälerergraben so vrstno razmeroma bogate. Prevladujejo rodoviDentalina, Ammodiscus, Nodosariain Glomospirella. Foraminiferne združbe iz Zlambach formacije v Rossmoos-/Stambachgraben profilu so podobno raznolike in številčne. Najbolj pogosti rodovi so Reophax, Dentalina in Annulina. V najvišjih delih Kössen formacije profila Schlossgraben prevladujejo foraminifere s hialinsko steno. Najbolj pogosti rodovi so Ichthyolaria, Lenticulina in Nodosaria. Zgornja Kössen formacija pri Fonsjochu vsebuje foraminifere rodov Lenticulina, Astacolus in Trochammina. Porast deleža oportunistov v vrhnjem delu Kössen formacije kaže na spreminjajočo količino kisika. V Kendlbach formaciji profila Schlossgraben prevladuje skupina Lagenida. Preostanek pripada aglutiniranim primerkom. Najbolj pogosti rodovi so Astacolus, Lenticulinain Trochammina. V profilu Fonsjoch Kendlbach formacija od foraminifer vsebuje večinoma rod Astacolus. Sledijo Trochammina, Ammobaculites, Reophax in Lenticulina. Porast v deležu oportunistov kaže na stresne pogoje. Tem kmalu sledijo bolje prezračene razmere in večji delež nodosariid.

• Keywords: zgornji trias, zgodnja jura, Pötschenkalk, Zlambach formacija, Kössen formacija, Kendlbach formacija, morfoskupina