Kronome, B., Boorová, D. & Olšavský, M., 2024: Geological structure of the Strelnica massif (Muráň Plateau, Central Slovakia) based on new biostratigraphical data and geological mapping [Geologická stavba masívu Strelnice (Muránska planina, stredné Slovensko) na základe nových biostratigrafických zistení a geologického mapovania]. Mineralia Slovaca, 56, 1, 71 – 86.

DOI: https://doi.org/10.56623/ms.2024.56.1.3

Abstract: The Strelnica massif is a part of the Muráň Plateau near Tisovec town. The massif is of prolonged triangular shape and is sharply defined by faults from all sides: the Muráň fault (line) on the SE side, the Mýto-Tisovec fault system from the SW side and a thrust/fault line with unclear character in the Martinová valley on the N side. The massif was supposed to be built by Lower to Middle Triassic carbonate complexes, however our new biostratigraphic data had proven that in fact most of these light grey carbonates belong mostly to Upper Triassic, which makes necessary the reinterpretation of the structure of the whole massif. Despite of new and more complicated structural interpretation, our new age data are in better agreement with earlier works from the Tisovec quarry as it was in earlier geological maps.

Our mapping works also confirmed, that the Strelnica massif itself is built by two facially very different blocks: a deep-water type of succession with Reifling and Raming type limestones and a strongly tectonically reduced succesion from probably lower Carnian up to Liassic age. These two blocks are in tectonic contact along a fault line and both are lying on the Lower Triassic shaley complex which forms the basal horizon of the Muráň nappe. The Muráň fault (line) is covered by Quaternary deposits in the aera, but in addition we suppose also at least two newer fault systems: a NNW-SSE normal fault system, parallel with the Mýto-Tisovec fault system in the Rimava valley and a roughly WNW-ESE system with probable sinistral strike-slip kinematics. Both systems were locally known from the Tisovec quarry, or the structural measurements from the Dielik cave in the NE part of the massif, however not mapped in the whole massif.

Key words: Strelnica massif, Muráň Plateau, Triassic, biostratigraphy