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Zden?k Pouba's knowledge of regional and local geology, his appreciation of local communities (most courses in the Carpathians), his friendly personality combined with his sense of humor, tales and narrations, his guitar, Slo- vak, Czech, miners' and trappers' songs, all this has had lasting impact on the participants, often with guests from distant countries, like Prof. C. Naganna from Bangalore or T. Nakamura from Osaka. From regional geology to base-metal, magnetite, kaolin and gold deposits, their ore-forming processes and sourc- es, from general and structural geology to volcanism, from metallogeny to mining overviews and problems related to research policy.

Soil, mine tailing, and waste dump profiles above three mesothermal gold deposits in the Bohemian Massif with different anthropogenic histories have been studied. Their mineralogical, major element, and arsenic (As) contents and the contents of secondary arsenic minerals were analyzed. The As-bearing minerals were concentrated and determined using X-ray diffraction (XRD) analysis, the Debye-Scherrer powder method, scanning electron microscopy (SEM), and energy-dispersive microanalysis (EDAX). The amorphous hydrous ferric oxides (HFO), As-bearing goethite, K-Ba- or Ca-Fe- and Fe- arsenates pharmacosiderite, arseniosiderite, and scorodite, and sulfate-arsenate pitticite were determined as products of arsenopyrite or arsenian pyrite oxidation. The As behaviour in the profiles studied differs in dependence on the surface morphology, chemical and mineralogical composition of the soil, mine wastes or tailings, oxidation conditions, pH, presence of (or distance from) primary As mineralization in the bedrock, and duration of the weathering effect. Although the primary As mineralization and the bedrock chemical composition are roughly similar, there are distinct differences in the As behaviour amongst the Mokrsko, Roudný and Kasperské Hory deposits.[PUBLICATION ABSTRACT]

Zircon ages (U-Pb, LA-ICP-MS) obtained from skarns in the Kutná Hora and Svratka units and in the Moldanubian Zone (Bohemian Massif) show significant variations between the lithotectonic units as well as among samples from individual localities. The ages fall between 310 Ma and 3.1 Ga. We suggest that such large spread is a result of both different zircon clastic grain sources and subsequent metamorphic histories. The oldest Neoarchaean to Neoproterozoic ages are interpreted as detrital zircon grains from pre-Cadomian basement. Pronounced age maxima between 600 and 520 Ma (late Neoproterozoic to early Cambrian) were found in skarn samples from the Moldanubian Zone, Svratka and Kutná Hora units. We interpret these as maximum ages of skarn precursor deposition. Apparent Cambrian-Ordovician-Silurian to early Devonian zircon ages were obtained from non-mineralized samples of the Moldanubian Zone and also in file Kutná Hora Unit. This wide temporal interval could reflect maximum ages of skarn precursors related to disintegration of abundant early Palaeozoic magmatic rocks, provided the zircons were not modified by later metamorphism or fluid circulation. The early Carboniferous ages are interpreted to result from strong Variscan HT metamorphism and subsequent circulation of post-metamorphic fluids. Zircons of this age are dominant in skarns with massive magnetite mineralization, while the non-mineralized samples preserve the older ages.

A large number of Variscan mesothermal gold deposits are located in the central part of the Bohemian Massif, close to the Central Bohemian Plutonic Complex. The Petráckova hora deposit has many features that distinguish it from other deposits in the region and suggest its mineralization is closely related to the late magmatic processes associated with the Petráckova hora granodiorite. The gold ores occur as sheeted arrays of quartz veins and veinlets hosted by the small Petráckova hora granodiorite stock. Gold is found mainly as free grains of >900 fineness, and is accompanied by abundant pyrrhotite and chalcopyrite, and accessory pyrite, arsenopyrite, loellingite, and molybdenite. Molybdenite from the Petráckova hora deposit has been dated by the Re-Os method at 344.4±2.8 Ma. Hydrothermal alteration in the Petráckova hora deposit exhibits a distinct temporal paragenesis. Selectively pervasive, early K-alteration and silicification are the oldest hydrothermal phases. These were followed by early quartz veins (Q^sub 1^ to Q^sub 4^) that contain most of the gold mineralization. Late quartz veins (Q^sub 5^) and fracture-controlled silicification are gold-poor or barren. Barren calcite veins are the youngest hydrothermal product. Extensive low-temperature, meteoric-water dominated alteration, as is typical of classic porphyry deposits, is absent. However, the lower [delta]^sup 18^O whole rock values for Petráckova hora granodiorite and aplite (+2.4 to +5.1[per thousand] SMOW) compared to other intrusions in the region reflect either interaction with isotopically light external fluids or magma assimilation of small volumes of hydrothermally altered country rock. The [delta]^sup 18^O isotopic compositions for quartz, scheelite and hornblende (7.7 to 13.4[per thousand] SMOW) and the [delta]^sup 34^S compositions for sulfide minerals (-1 to +3.5[per thousand] CDT) from early, gold-rich quartz veins indicate formation at high temperatures (590 to 400 °C) from fluids with a magmatic isotopic signature ([delta]^sup 18^O^sub FLUID^ of 5.7 to 7.2[per thousand]). Fluids related to late quartz veins (Q^sub 5^) suggest the presence of a significant component of non-magmatic water ([delta]^sup 18^O^sub FLUID^: +2.5 to +4.0[per thousand]). The [delta]^sup 34^S values of post-Q^sub 5^ sulfide minerals (-4.5 to -3.5[per thousand]) reflect at least partial derivation of late-stage sulfur from a source external to the intrusions. Aqueous, aqueous-carbonic and nitrogen-bearing fluid inclusions were identified in hydrothermal and igneous quartz, with the aqueous inclusions being the most common. In hydrothermal vein quartz, the salinity of primary aqueous inclusions falls into ranges 6 to 23 and 33 to 41 equiv. wt% NaCl; in igneous quartz, populations in salinity were observed between 5 to 16, 35 to 40 and 62 to 70 equiv. wt% NaCl. The salt component of these fluids is best, and minimally, approximated by the NaCl-KCl-CaCl^sub 2^ system. Low- and high-salinity aqueous-carbonic inclusions are accessory in many of the analyzed samples. Three large successive pulses of fluids are recognized. Each pulse begins with a high-salinity (>30 equiv. wt% NaCl) magmatic fluid and evolves toward a lower salinity (~5 equiv. wt% NaCl) fluid. Data suggest that external (meteoric?) water(s) were significant for only the third fluid pulse, which formed the late Q^sub 5^ quartz veins and the calcite veins. Polyphase fluid inclusions hosted by igneous quartz of the Petráckova hora granodiorite indicate minimum trapping conditions of about 3 kbar and 550 °C. The gold-rich Q^sub 1^ to Q^sub 4^ veins may have formed along a quasi-isobaric cooling path at 2.5 to 1.5 kbar and 590 to 400 °C. This was followed by uplift, and formation of late Q^sub 5^ quartz veins (0.5 to 1.5 kbar; ~300 °C) and post-ore calcite veins (<0.5 kbar; 100 to 140 °C). The characteristics of the Petráckova hora deposit suggest that it may represent a position intermediate between intrusion-related gold systems (e.g., Fort Knox deposit, Alaska) and gold-rich, copper-poor porphyry deposits (e.g., Maricunga Belt in Chile). As such, the Petráckova hora deposit might be an example of the reduced gold sub-type of porphyry deposit.[PUBLICATION ABSTRACT]

his report deals with various inequalities and their correlates, effects and causes in the Czech Republic and Slovakia over the recent decades, focusing mainly on the 1990s and 2000s. Its main objective is to provide a comprehensive account of changing inequalities in income, wealth and education over time and their social, political and cultural impacts in the two republics. The Czech Republic and Slovakia as transforming economies experienced an increase of inequalities mainly in the beginning of the 1990s. The increase of inequality in both republics was a palpable output of the transformation process. However, it may have also resulted from the monetization, and thus improved measurability, of inequalities existing already before 1989 in different forms (e.g. access to certain goods or services not accessible to the general public). It should be emphasized that the level of inequality, after its growth in the 1990s, remained relatively stable and lower compared to other transforming countries in the 2000s. This is mostly a consequence of redistributive policies which alleviated the impact of transformation on low-income groups.