An electron microprobe study of polished sections prepared from a sample of fine-grained sandstone from the locality Slivotín (Ždánice-Hustopeče Formation, Ždánice Unit, Flysch Belt of the Outer Western Carpathians, Czech Republic) allowed to yield in addition to data on chemical composition also the detailed information on in situ textural relationships of individual minerals. During our study, emphasis was given to accessory phases belonging to the translucent heavy mineral fraction. The detrital garnet (Alm36-82Grs2-45Prp2-22Sps0-15) was extensively dissolved and replaced by calcite cement from its margins and along the cracks. Detrital fluorapatite was dissolved in a similar way, however, dissolution episode was followed by growth of authigenic rims composed of carbonate-fluorapatite. Other observed heavy minerals (zircon, chrome spinel, TiO2 phase, monazite, tourmaline) probably remained unaltered by diagenetic processes. The chemical composition of chrome spinels varies mostly between magnesiochromite and chromite, whereas spinel is very rare. The chemical composition of garnets and chrome spinels is comparable with published data from Czech, Polish and Slovak parts of the Flysch Belt of the Western Carpathians, and indicates the primary source of detrital material in rocks of deeper parts of orogen, characterized especially by the presence of catazonal metamorphites and almost lacking volcanic rocks. Redeposition of heavy minerals from older sediments cannot also be ruled out. The pronounced diagenetic alteration of garnet, if not very scarce in the area of Flysch Belt, could help to explain the earlier observations of wide fluctuations of contents of garnet in heavy mineral concentrates.

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This article brings new information about phenomenon of the growth of floodplain forest without influence of floods over 50 years. Floodplain forest and its hydrogeological regime are under detail research for 10 years and detail 10 years data from hydrogeological well is used in this study. The area of interest belongs to nature reserve Plackuv les what together with brook Satava represents a unique relic of a floodplain forest in the confluence area of the rivers Svratka and Jihlava in southern Moravia (South‑Moravian Region). The damming of the channel of the river Svratka has caused the end of floods. Despite the anthropogenic regulations performed, the hydrogeological conditions have remained preserved at the site. Stream channel was rised due to the regulation at the above the level of the existing ground; this eliminated its drainage functions for groundwater. The contact between the base of floodplain loams and the groundwater Tab. is not lost and the capillary rise in them remains preserved. Analysis of groundwater level confirmed multi‑component refilling of the hydrogeological structure, which is drained in Plackuv les and the river Satava. All last 10 years, the maximum of the groundwater level measured is from July to September. It means, that groundwater reaches the highest level in the period, when the minimum flow rates are recorded on the surface flows. In this period, the locality displays the maximal infiltration of the precipitation from the last hydrological year from distant infiltration area. Because of the absence of floods, groundwater at this site is the most significant resource of water, and it represents a key‑factor which enables the growth and thriving of the floodplain forest ecosystem.

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The interfacial transition zone is one of the weakest areas in concrete. Microcracks and new phases often form in this zone, affecting the resulting concrete’s mechanical properties. In this research, concrete in which Portland cement was partially replaced by powdered limestone and/or metakaolin was cured for 1 and 28 days and then mechanical properties were tested. The interfacial transition zone was studied by scanning electron microscopy and selected phases were analyzed by electron microprobe. The addition of a small amount of limestone or metakaolin increases the strength of the concrete. The strength significantly decreases with a content of 10% or more supplementary cementitious materials (SCMs) in concrete. The microcrack’s thickness at the binder-aggregate interface reaches up to 0.8 μm. In concretes with limestone, rhombohedral calcite crystals up to 0.5 μm in size accumulate in the interfacial zone. This accumulation can significantly reduce the strength of the concrete when the amount of limestone is high. Zeolites with a composition corresponding to Mg-mazzite are formed at the interface of cement paste, quartz and albite, partially replaced by sericite.

(25-11 Hlubočky) ÚvodLokalita Zlatý důl se nachází v kulmu Nízkého Jeseníku, konkrétně v moravickém souvrství, cca 9 km sv. od Olomouce. Ve středověku se zde těžily polymetalické Cu-Pb-(Au?)-(Ag?) rudy, zejména galenit, ze kterého bylo získáváno stříbro (Novák -Štěpán 1984). Horninové prostředí v okolí lokality je reprezentováno kulmskými sedimenty (klastika spodního karbonu), převážně jílovými břidlicemi a prachovci, které se střídají s polohami drob. Podél potoka Zlatý důl, který je pravostranným přítokem řeky Bystřice, můžeme nalézt haldičky s úlomky hydrotermální žiloviny. Hlušina žil je křemenná, křemen-karboná-tová či karbonátová. Sulfi dické minerály jsou zastoupeny hlavně chalkopyritem a galenitem, méně pak sfaleritem a pyritem. Nalezen byl i primární chalkozín (Novotný -Pauliš 2006), anatas (Zimák 1984), baryt a minerály vzácných zemin (synchysit, xenotim a minerály skupiny crandallitu) (Dolníček 2010;Kotlánová 2015). Na žilách ve Zlatém dole byly zjištěny dvě generace křemene. Starší mléčně bílý hrubozrnný křemen tvoří samostatné žíly a z rudních minerálů je na něj vázán pouze galenit. Mladší křemen je našedlý, jemnozrnný až středně zrnitý, uzavírá v sobě chalkopyrit a další sulfi dické minerály. Z karbonátů je hojný dolomitický karbonát, který svým chemickým složením odpovídá dolomitu až Fe-bohatému dolomitu ( Metodika a materiálNa haldách ve Zlatém dole byly v letech 2012-2015 odebrány vzorky žiloviny k následnému studiu. Z reprezentativních vzorků byly vyhotoveny oboustranně leštěné destičky. Mikrotermometrická měření byla provedena na aparatuře Linkam THMSG 600 instalované na polarizačním mikroskopu Olympus BX-51 na Katedře geologie PřF UP v Olomouci. U inkluzí byly měřeny následující parametry: T f -teplota zamrznutí, T h -teplota homogenizace, T mice -teplota tání posledního krystalku ledu a T e -teplota eutektika. Salinita byla vypočítána dle Bodnara (1993). Pro genetické typy fl uidních inkluzí byly použity