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The Pannonian basin is a major geothermal heat system in Central Europe. Its peripheral basin, the East Slovakian basin, is an example of a geothermal structure with a linear, directed heat flow ranging from 90 to 100 mW/m2 from west to east. However, the use of the geothermal source is limited by several critical tectono-geologic factors: (a) Tectonics, and the associated disintegration of the aquifer block by multiple deformations during the pre-Paleogene, mainly Miocene, period. The main discontinuities of NW-SE and N-S direction negatively affect the permeability of the aquifer environment. For utilization, minor NE-SW dilatation open fractures are important, which have been developed by sinistral transtension on N–S faults and accelerated normal movements to the southeast. (b) Hydrogeologically, the geothermal structure is accommodated by three water types, namely, Na-HCO3 with 10.9 g·L−1 mineralization (in the north), the Ca-Mg-HCO3 with 0.5–4.5 g·L−1 mineralization (in the west), and Na-Cl water type containing 26.8–33.4 g·L−1 mineralization (in the southwest). The chemical composition of the water is influenced by the Middle Triassic dolomite aquifer, as well as by infiltration of saline solutions and meteoric waters along with open fractures/faults. (c) Geothermally anomalous heat flow of 123–129 °C with 170 L/s total flow near the Slanské vchy volcanic chain seems to be the perspective for heat production.

Argentiferous Strieborna vein of the Rožňava ore field occurs at the southwestern margin of the Gemeric Unit (Slovakia). The hydrothermal mineralization of the vein closely related to the Early Cretaceous tectonometamorphic shortening of the Western Carpathians. For their emplacement, the vein used the steeply dipping, fan-like cleavage and dislocation set of the Alpine regional structure. Successively the vein was integrated into the sinistral transpressional regime of the Transgemeric shear zone. A polyphase vein filling comprises Variscan metasomatic siderite remnants and the Early Cretaceous syntectonic hydrothermal mineralization, the latter consisting of two mineralization phases, quartz-siderite and quartz-sulphidic. During Cretaceous shear zone transpressional events, the vein was segmented into five individual bodies and redistributed to kinematically and geometrically different tensional and compressional boudins. The vein asymmetry increase, different vertical mineralization content and spatial distribution of mineral phases representing individual mineralization periods directly relate to a rheological contrast between the vein and surrounding rocks stress and pressure shadows distribution. The actual form and distribution of the Strieborna vein segments is the product of four boudin evolution stages: (1) pre-deformation, (2) initial, (3) boudin-forming and (4) boudin-differentiation stage that controlled vertical mineralization distribution. The sulphidic mineralization is dominated by two generations of argentiferous tetrahedrite and two youngest sulphosalts associations enriched by Sb and Bi. The youngest sulphosalts of the stibnite phase at the Strieborna vein resemble contemporaneous mineral associations at the nearby Čučma stibnite vein lode. Both vein occurrences located within the Transgemeric shear zone belong to the Rožňava ore field and they are cut by the same diagonal strike-slip fault. These analogies indicate a similar genesis of terminal associations at both these vein deposits. Results of the Strieborna vein sulphosalts spatial analysis confirm their vertical zonation. The Sb and Ag contents decrease, while Bi contents increase, with depth and conserve boudin evolution stages created in distinct rheological environments. The vertical boudin arrangement concentrates economically most prospective parts into asymmetric boudin tension shadows.

Thick deep-wa ter sand stone suc ces sions are known from many lo cal i ties in the Outer West ern Carpathians. The pres ent study is fo cused on com par i son of de pos its of the Piwniczna (PwSM) and Poprad (PpSM) Sand stone mem bers be long ing to the Magura For ma tion of the Magura Unit, out crop ping in the east ern Slovakia and Po land bor der area. At the gen eral level, a close sim i lar ity of the sand stone suc ces sions was con firmed by this study. How ever, in more de tail, fa cies anal y sis shows dif fer ences in the thick ness of the sand stone suc ces sions, in grain size and in the char ac ter of in ter vals be tween the thick sand stones. Thin-sec tion study, though, showed al most the same modal com po si tion in the sand stones ana lysed. The sand stone suc ces sions stud ied are in ter preted as sandy debrites, the PwSM show ing tran si tional fa cies to turbidites. These de pos its rep re sent channelized depositional lobes in the prox i mal part of a sub ma rine fan with the PpSM closer to the source. The sed i ment source area was com mon to both lithostratigraphic units, and was most likely the South-Magura Ridge.

Strong tectonic remobilisation and shear zone development are typical features of the easternmost part of the Veporicum tectonic unit in the Western Carpathians. The granodiorite mylonites in the area of the Rolovská shear zone (Čierna hora Mts) underwent a complex polystage evolution during the Hercynian and Alpine orogenies. Deformation during the latter reached greenschist facies under metamorphic conditions. Mylonites are macroscopically foliated rocks with a stretching lineation and shear bands. Structurally different mylonite types, ranging from protomylonites to ulramylonites with typical grainsize reduction from the margins towards the shear zone centre, have been assessed. The modal mineralogy of the different mylonite types changes considerably. Typical is a progressive decrease in feldspar content and simultaneously the quartz and white mica content increases from protomylonites towards the most strongly deformed ultramylonites. The deformation had a brittle character in less deformed rocks and a ductile one in more deformed tectonites. Obvious chemical changes occur in mesomylonites and ultramylonites. During mylonitisation, the original biotite granodiorite was depleted of Mg, Fe, Na, Ca and Ba, while K, Rb and mainly Si increased considerably. Other (major and trace) elements reflect erratic behaviour due to lateral mobility. Chemical changes indicate the breakdown and subsequent recrystallisation of biotite and feldspars and, in turn, the crystallisation of albite and sericite. REE decrease in ultramylonites due to the breakup of accessory minerals during deformation and alteration.