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The paper brings new knowledge about the occurrence of carbonate breccias and conglomerates structurally incorporated into the Hronic and Fatric nappe stack in the southeastern part of the Strážovské vrchy Mts. Carbonate breccias to conglomerates have the character of tectonites, but locally the tectonic impact is not penetrative and the original sedimentary structures can be observed. Their age is not biostratigraphically documented. On the basis of the lithological character and regional context, however, their Paleogene age can be assumed. Breccias and conglomerates were observed in the area of the Veľký Čihoc massif (NW of Nitrianske Sučany) and in the thrustsheets in the area of the west of Diviacka Nová Ves and in the area between Nitrianske Sučany and Horné Vestenice, where they separate apparently continuous sedimentary sequences. Geological mapping as well as structural research (slickensides) reveal southeastern to eastern vergence of thrusting and reverse faulting. Such structures are considered as backthrusts and are recognized in this area for the first time. The rocks of the Mraznica Formation of the Fatricum are accompanying almost regularly the backthrusts. The inverse position of the Fatricum above Hronicum underlines the significance of these Post-Paleogene tectonic events.

On the basis of systematic revision mapping the thesis reports the real state of representation of the Permian sedimentary formation in the Tatric tectonic unit in the Nízke Tatry Mts. Permian deposits later called the Vážna Formation, were reported in the area of the Vážna valley in the 1980s. The Permian deposits depicted on two regional geological maps have been revised over a period of more than a decade. Revision mapping from the Baláže and Trangoška areas did not confirm presence the Vážna Formation. Permian deposits outcrop in the Okrúhly vrch area but do not belong to the Tatricum tectonic unit. The studied sediments belong to the newly defined Stupka Member of the Malužiná Foramation. Permian deposits in the crystalline basement of the Nízke Tatry Mts. have been confirmed at only one of the three originally revised sites, namely in the area of the Javorie saddle. At the same time, the emendation of the term Vážna Formation to the Javorie saddle Formation is recommended

Geological structure of the Vrátna dolina Valley in the Krivánska Malá Fatra Mts. is composed of two main Western Carpathian tectonic units – Tatricum and Fatricum (Krížna nappe). Tatricum is represented by almost all common lithostratigraphic members, although mainly the Jurassic and Cretaceous sediments are either strongly reduced, or completely missing. Based on our field observation, sedimentary cover is thrusted over its own crystalline basement accompanied by the reduction of lowermost sedimentary formation – Lúžna Fm. Situation in the Krížna nappe rock sequence is even more extremly reduced. Radiolarian limestone of the Ždiar Fm. (Oxfordian) is the oldest lithostratigraphic unit. This causes considerable problems in defining the stratigraphic range of the particular units. We have defined the individual rock members into tectonic units on the basis of lithological character, because tectonic repetition or superposition of sedimentary sequences was not observed. All rock members form one apparently continuous sequence with stratigraphic range from the Paleozoic to the Early Cretaceous. We present different interpretation of the geological setting on the ridge under the Vrátna ropeway. Chaotic configuration and/or repetition of the Triassic members were documented in the older maps, which could indicate assumed folding or duplex structures. However, we suppose that these complications are the result of younger slope deformation, rather than the older tectonic deformations.

The presented work summarizes knowledge on the Lunz Beds in the Hronic Považie and Ostrá Malenica nappes of the eastern portion of the Strážovské vrchy Mts. It is based mainly on the results of fild research and geological mapping in the area of the Zliechovská hornatina and Nitrické vrchy Mts. The studied rocks are mainly gray-green or brown sandstones, and locall gray-green siltstones or grey claystones. The sandstones are usually structureless (massive) or laminated, thin- to thick bedded. Contain coalifid plant remains, ichnotaxa Arenicolites isp., Phycodes isp., Planolites isp. and Thalassinoides isp. and siltstone or claystone intraclasts. Petrographically, sandstones represent micaceous subarkose, lithic wacke, less often feldspathic (arkosic) wacke and sublitharenite. The observed vitrinite reflctance values 0.95–0.97 % Ro indicate a relatively high diagenetic transformation of the Lunz Beds, where the maximum temperatures reached 131–150 °C. Such conditions were probably achieved during the tectonic burial of the rocks within the nappe structure and later subsidence due to the deposition of superimposed (post-nappe) sediments of the Cenozoic basins.

This work deals with the lithostratigraphy of the Permian Malužiná Formation of the Hronic tectonic Unit in the Bystrá area in the Nízke Tatry Mts. The lithostratigraphic study was based on the detailed field study during reambulation of the geological map in this area. Based on observed lithological and sedimentological features the studied rocks were correlated with the upper part of the Malužiná Fm. from the northern part of the Nízke Tatry Mts. A new member – Stupka Beds (new term) ‒ has been described and defied in the Bystrá area. The Stupka Beds represent forth coarse-grained horizon of the Malužiná Fm. Type localities of the Stupka Beds are situated in the Stupka hill area, where they occur above the andesitic basalts and below the Lower Triassic deposits. A characteristic feature of the Stupka Beds is the presence of rhyolitic detritus in cm to dm grain size range. Another new fiding is an occurrence of a rhyolitic ignimbrite body in the Hnusné Valley. Rhyolites occur in a tectonic position relative to the surrounding rock sequences. Acid volcanites are rare in the Hronic nappe units. It invokes an affity of the studied section of the Hronic Unit to the Drienok, Muráň and Vernaric nappe units.