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The article presents the first description of a complete and continuous series from berthierite to garavellite sulphosalts in the Western Carpathians. Berthierite is a common main or accessory phase of Sb mineralizations in the Western Carpathians, and occurs at many localities and ore deposits as well. On the other side, garavellite or Bi-rich berthierite is a relatively rare accessory phase. The highest Bi content in garavellite reaches up to 38.04 wt. % which represents 0.90 apfu, and its crystallochemical formula can be written as Fe0.97Sb1.07Bi0.90S3.98. Raman band shifts were observed in the isomorphic berthierite–garavellite series. Garavellite occurs in the younger stages of sulphidic mineralization, and associates with tetrahedrite, berthierite, Bi-chalcostibite, Sb-bismuthinite, Bi-stibnite, ullmanite and cinnabarite. It creates irregular grains and veinlets in pre-existing tetrahedrite, or forms myrmekite intergrowths with chalcopyrite in tetrahedrite. Bi content in chalcostibite is up to 0.20 apfu. Besides the tetrahedrite, pre-existing sulphosalts are the members of the tintinaite–kobellite series, Bi-jamesonite and bournonite. The Sb/(Sb+Bi) ratio of minerals of the tintinaite–kobellite series varies from 0.37 to 0.80. The maximum content of Bi in jamesonite is up to 1.22 apfu. A vertical zonation at the ore vein body (mining levels 6 / 180 a.s.l., 8 / 80 a.s.l., 10 / 20 b.s.l.) is represented by the Sb decrease along with the Bi increase with increasing depth. Bi content continuously decreases during the older ore mineralization stage and Sb increases at the younger mineralization stage. Both of the stages have been enriched by Sb as well.

During the Alpine convergence of the Central Western Carpathians, a set of subparallel NW-SE shear zones formed in the eastern part of the Veporic Unit, near the tectonic contact with the Gemeric Unit. Deformation in low-grade metamorphic conditions was typical of the Alpine movements in the shear zones. Mylonitic rocks of the crystalline complex and their cover formations were studied on a macro and micro scale to characterise the evolution of deformation structures in the shear zones. The differential stress of dynamically-recrystallized quartz, which aggregates in mylonitic rocks, was determined using quartz paleopiezometry. Several types of foliation structures, but mainly penetrative subhorizontal stretching lineation in all observed mylonites, provide evidence of stretching and oriented ductile flow in a NW-SE direction. Shear sense indicators show the subhorizontal movement of the shear zone hanging walls to the SE. Dynamically-recrystallized quartz aggregates in the mylonitic rocks show different values of grain sizes and differential stresses, depending on the structure in which they occur. The lowest differential stresses were found in the quartz aggregates parallel to the S planes of the mylonites. Higher values are related to the C shear bands. The character of the structural setting indicates the formation of the shear zones in the orogen-parallel extension conditions. [ABSTRACT FROM AUTHOR]

Uranium ore mineralisation occurrences at the Western Carpathians/Slovakia are deposited within Permian volcano-sedimentary sequences. The mineralisation principally consists of two genetic types, the stratiform one and U-Mo vein mineralization linked to andesite volcanites. Geological exploration of uranium mineralization in Slovakia is subject to rigorous assessment of Ministry of Environment and municipalities. The limited energy sources and dependence to foreigner, open space for prospection of new energy sources (reneweable, uranium or traditional from coal, oil, gas).

The mining science, unlike many other technical sciences, studies the processes that occur not in one place, but in moving faces. The primary task is to analyze the influence of the various factors defining the parameters of the quarry operational area and to define a possibility of mining operations’ concentrating on the individual sections of the quarry, taking into account their further development downdip and in-depth. The intensity of their movement depends on the surface and on the excavating equipment capacity. The development of open pit mining area in time and space is subject to certain rules. Thus, the initiating works providing the access to the deposit should be ahead of the work on the preparation of excavation blocks, and the latter coal extraction. The intensity of the implementation of this works is also associated with certain patterns of the quarry working area development. The article describes the calculation method for determining the cyclical size of the working area, as a function of some key points: the time of working area development; its speed vector; the direction of the depth of mining and the quarry field area.

NW-SE faults has plaged a decisive role in the Alpine development of the eastern margin of the Wes-tern Carpathian Internides. Both the space position of rock sequences and morphostructural pattern of the Gemeric and Veporic units of the area are principally controlled by their network. One of the essential Western Carpathian discontinuities of the region - the Margecany shear zone, i.e. the boundary between the Gemeric and Veporic units belongs to this fault set. Three following activity stages have been recognized within the Alpine development of the NW-SE faults: (i) - the Cretaceous stage, (ii) - the Neogene stage, (iii) - the Quarternary stage. Within the Cretaceous stage two development phases of the fault set activity has been verified. The Early Cretaceous - the compressional semi-ductile one, is connected with overall the north-vergent crustal reduction of the Western Carpathian Internides. The Late Cretaceous - the extensional stage exemplified by a postkinematic recrystalization of the previous tectonites is bound to the ongoing upheaval of the Western Car-pathian Veporic dome. The Neogene fault set activity iniciated likely by the eastern escape of the Western Carpathians is ma-inly typical by strike - slip motion of reactivated and/or newly created NW-SE fault structures. The Quarternary - up to the recent activity of the faults includes predominantly vertical motions.

WNW - ESE horst of Mesozoic sequences of the Humenské vrchy Mts. forms NE margin of the East-ern Slovakian basin filled by Neogene vulcanosedimentary formations. They consist of Middle Triassic (Ani-sian) to Middle Cretaceous (Lower Cenomanian formations) belonging to Križna superficial nappe unit of the Western Carpathians. Structurally the sequence is composed of four directional sheets (i.e. Jasenovská, Klako-činy, Kocovo, and Hôrka sheet) dipping to N - NNE. The sheet structure has been formed during Miocene back-ward thrust of the Paleogene flysch formations. Other dislocations of the same and N - S direction are of younger age. They are bound to final formation of Eastern Slovakian basin and they segment the horst to individual elevation and normal fault blocks.

Significant knowledges about litostratigraphical, structural and tectonometamorphic development of the Branisko-Čierna hora region have been abtained during creation of geological map of the region at the scale of 1:50 000. Some of them affecting general opinions about the Variscan and Alpine development of the Western Carpathian Internides are discussed in this contribution.

Basic information about outstanding geological localities of the Èierna Hora Mts. (i.e. the Veporic domain of the Central Western Carpathians) are presented in this contribution. At the first locality, nearby Margecany village, the Margecany shear zone, i.e. the tectonic contact of the Gemeric and Veporic unit, is observable. At the second one, situated northwards from the Koické Hámre bridge, a nearly complete cross-section of cover formations of the Èierna hora basement is outcropped. Infolding of cover stratas into basement metamorphites and sucessive imbrication of both mentioned formations are instructively developed at the third locality, the Ruín dam area.

We would like to welcome you to the excursions finalizing the Geology and prospecting in the Carpathians Conference, Her¾any 2000. The aim of the excursions is to provide you an overview of these Western Carpathian lithostructural units and their mineralization respectively, research progress of which has been (at that time) closely connected with personal investigation enthusiasm of our Professors - the founders of our Faculty. The current state of geological development knowledge of principal structural units of the Western Carpathians is outlined in papers included in special issue of Mineralia Slovaca magazine you have received at the begining of the Conference. For this reason the content of this Excursion quide is exclusively concentrated to description of routes localities. Broader geological relationships of particular outcrops is possible to find in attached Geological map of the Slovak Republic 1:100 000. The organizers of the excursions gratefully acknowledge the efforts of all colleagues who contributed to this quide. We also like to express our thanks for the financial support to Slovak VEGA grant Agency (Grant No:1/7389/2) and to the following organizations: Association of Metallurgy, Minig Industry and Geology of Slovak Republic, Slovak Geological Society, Management of TU Koice, SAPTU Foundation of TU Koice, Geological Survey of the Slovak Republic Betox JSC. Koice, SMW JSC. Jelava, Uranpress Ltd. Spiská Nová Ves, TESCO Koice, ELBA-Siderite JSC. Niná Slaná and ELBA JSC. Spiská Nová Ves.

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. [ABSTRACT FROM AUTHOR]

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The Silica nappe forms the rear paleoalpine nappe structure of the Alpine orogeny in the Central Western Carpathians. The main period of the nappe formation relates to a spatial convergence from the south to the north. During the Early to Late Cretaceous, the position of this nappe as well as its structural core elasticity reflect an uplift of the Silica nappe pile and consequently its weathering and karstification. After that, inner karst structures were injected by concentrated aqueous solutions from which Fe, Mn (±Ni) nodules and crusts have been precipitated. This stage of nodules/crusts deposition reflects anoxic conditions. Ongoing bulging of the Silica nappe caused an increase of the karstification rate and locally also its connection to the surface. Implicitly conditions for the clastic sedimentation were formed and deposition of the Gombasek beds was initiated. The Late Cretaceous paleoclimate could be characterised by small temperature variations during the year and only seasonal rainfalls what is also indicated from the composition of the Gombasek beds reflecting quiet water conditions with recurrent sediment inflows. Limestone clasts incorporated to the upper part of analysed sedimentary record most likely relate to the tectonic activity increase during Late Cretaceous thrusting. [ABSTRACT FROM AUTHOR]

The method of paleopiezometry reveals new pleopiezometric data of differential stresses σ (σ1 - σ3; MPa) within the calcite veins in outcrops with developed fold structure near the village of Chmeľnica - eastern sector of the Pieniny Klippen Belt - PKB (the Inner Western Carpathians - IWC ). The results of paleopiezometric investigations on deformed calcite veins from the PKB at Chmeľmica village within ductile deformed host rocks representing numeric data about the differential stresses from the final stages of ductile deformation of the calcite veins, penetrating the whole volume of host rocks. The number of deformation twins per 1 mm of the perpendicular diameter of the grain (D=31-52) at the grain-size (450.5-516 µm) has been produced by the recrystallization at differential stresses σ = 203.48-228.44 MPa. The new results are given for comparison with previous ones, related with subducted and consequently exhumed rock blocks belonging to Jurassic Mélange proven from the southern Northern Calcareous Alps (NCA) - Hallstatt and Tirolic unit in the Eastern Alps (EA) (184.15-233.88 MPa) and the Meliatic Unit from the frontal parts of the Bôrka nappe, thrusted over the Gemeric Supernit in the IWC (347.49-439.55 MPa). Both measured units are representing the parts of the Jurassic Neotethyan Belt, striking from the Carpathians to the Hellenides. The difference between differential stresses simultaneously indicates that the total dynamic recrystallization of allochthonous marbles from the Kurtová skala hill should occur in conditions of the subduction zone, but their post-exhumation transport on autochthonous carbonates without their whole-volume plastic deformation should occur in "could conditions" corresponding with the transport of the superficial nappe. The high differential stresses caused the origin of deformation twins nearly in each calcite grain (Twinning Incidence up to 100 %), as well as the high no. of deformation twins per 1 mm of the perpendicular diameter of the grain (D = 173.0 -646.25) was developed to the very small size of grains (23.7-42.7 µm). These results of differential stresses represent the highest values until found in the Inner Western Carpathians. The numeric paleopiezometric data obtained from the eastern sector of the PKB, as well as from the area of Pailwand, were measured in ductile deformed calcite veins, manifest the pressure conditions tightly before the "frozing" of the ductile deformation state at the final stage of thedeformation process. That mirrors not only in the markedly lower values of differential stresses, but also in the grain sizes of thin-sections within calcite veins from the PKB - the IWC (450.5-516 µm), as well as from the oceanic fragments of the Pailwand, the NCA, the EA (323.38 - 571.25 µm), which are much coarser in comparison with grain sizes of thin-sections from Bôrka nappe (23.7 - 42.7 µm; but also 174.0 - 403.20 µm in the case of grains, which undergone the static recrystallization in the rear parts of the Bôrka nappe). Based on all these measurements, the method of paleopiezometry seems to be a usable tool for determination of differential stresses, which contribute to reveal a geological and tectonic interpretation of geodynamic history. [ABSTRACT FROM AUTHOR]