The Gogolin Formation is a Triassic geological formation in southern Poland, representing the lowermost lithostratigraphic unit of the Lower Muschelkalk within the Silesian‑Cracow Upland. It overlies the Upper Buntsandstein (Lower Triassic) carbonates and is overlain by the Górażdże Formation of the Middle Triassic. The formation is named after the town of Gogolin, where its type sections were first described and where the principal stratotypes are exposed【r.jina.ai/http://en.wikipedia.org/wiki/Gogolin_Formation】.
Age
The formation was deposited during the latest Olenekian (Late Early Triassic) or earliest Anisian (Early Middle Triassic), extending into the Pelsonian substage of the Anisian【r.jina.ai/http://en.wikipedia.org/wiki/Gogolin_Formation】.
Lithology and Depositional Environment
It consists chiefly of carbonate rocks laid down on a shallow carbonate ramp. The succession includes a variety of limestone, marl, and dolomitic facies, with both bioclastic (crinoidal, gastropod, brachiopod) and micritic components. The carbonate ramp setting indicates a shallow marine environment with periodic influxes of terrigenous material.
Stratigraphic Subdivision
Recent work has divided the Gogolin Formation into four members, six beds, and two horizons:
- Zakrzów Crinoidal Limestone Member – comprising pelitic limestone, bioclastic limestone, and graded limestone beds.
- Skała Marl Member – marls interbedded with micritic and bioclastic limestones; includes intra‑formational conglomerates.
- Emilówka Cellular Limestone Member – characterized by massive bioclastic limestones and dedolomitized dolomites.
- Odrowąż Marly Limestone Horizon – marly limestones with bioclastic interbeds.
Additional horizons include the Malnia limestone horizon and the Ligota Hill wavy‑bedded limestone member, each distinguished by specific bedding and fossil content.
Geographic Extent and Type Localities
The formation is documented in outcrops around Gogolin and nearby localities such as Błotnica Strzelecka and Ligota Dolna in Opole Voivodeship, Poland.
Significance
The Gogolin Formation records early Middle Triassic marine conditions in Central Europe and provides important fossil assemblages, including crinoids, conodonts, and early marine reptiles, that aid in regional correlation of the Muschelkalk succession.
Sources: Wikipedia entry “Gogolin Formation” (accessed via Jina AI mirror).