Aubrecht R., 2023: Palaeokarst clefts and their filling at the type locality of the Honce Limestone (Turňa Unit): Petrographic analysis and its preliminary interpretation. Acta Geologica Slovaca, 15, 2, 95–105.

Palaeokarst clefts and their filling at the type locality of the Honce Limestone (Turňa Unit): Petrographic analysis and its preliminary interpretation

Roman Aubrecht^1,2

¹Department of Geology and Paleontology, Faculty of Natural Sciences, Comenius University, Ilkovičova 6, SK–842 15 Bratislava, Slovakia; roman.aubrecht@uniba.sk
²Earth Science Institute, Geophysical Division, Slovak Academy of Sciences, Dúbravská cesta 9, SK–845 28 Bratislava, Slovakia

Abstract

Palaeokarstic cavities and clefts, filled with sedimentary material, were discovered in the marble quarry near Honce village in the Gemer area. The wall rock is the Honce Limestone, a marble formed by the metamorphism of the Lower Anisian Steinalm Limestone of the Turňa Unit. Analysis of the cavity fillings revealed that initially, they were filled with laminated calcarenites from the wall rock marbles, which later transitioned to siliciclastic sandstones and siltstones. The final filling consists of oligomictic breccias, dominated by non-metamorphosed sandstones and claystones, suggesting that the Lower Triassic Bódvaszilas Formation is the most likely source. This formation represents the basement of the Silica Nappe thrust onto the Turňa Unit. The filling of the clefts likely reflects the thrusting process, most plausibly estimated to occur during the Late Cretaceous to Palaeogene period.

Key words: Turňa Unit, Silica Nappe emplacement, palaeokarst, Lower Triassic

Manuscript received: 2023-11-21

Revised version accepted: 2023-12-20