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ACTA MUSEI MORAVIAE - SCIENTIAE GEOLOGICAE 92/2007
Abstract
Fojt B., Dolníček Z., Hoffman V., Škoda R., Trdlička Z., Zeman J., 2007: Paragenetická charakteristika
ložisek Zn–Pb rud v širším okolí Horního Města u Rýmařova. Acta Mus. Moraviae, Sci. geol., 92, 3–57.
Paragenesis of the Zn–Pb ore deposits in the wider neighbourhood of Horní Město village near Rýmařov in Jeseníky Mts. (Czech Republic)
The ~7 km long mineralized zone of the Horní Město ore district is situated in southern section of the Vrbno
Group. This Devonian volcano-sedimentary sequence is a part of Rhenohercynian Zone at the eastern margin
of the Bohemian Massif. The stratiform sulphidic ores form lenticular bodies embedded in the so called
“Horní Město volcanic complex” (URBÁNEK and VALENTA 1989). The host rocks are bimodal volcanites, which
are characterized by a distinct predominance of trachytes, less rhyolites, and their pyroclastics. Basic volcanites
(containing small iron ore deposits) are already situated out of the mineralized zone in question. The
psammitic and psefitic sediments are rare. The whole area was subject of several deformations and
metamorphic events during the Variscan orogeny. The metamorphic overprint achieved the lower greenschist
facies, namely its chlorite zone. The least metamorphosed rocks are typically trachytes. The geotectonic setting
of the studied area is still under debate, but the most recent detailed petrological investigations classify the
igneous rocks as “alkaline rock suite derived by back-arc rifting” (JANOUŠEK et al. 2006).
The well elongated lenticular ore bodies contain sulphide minerals, whose distribution may be characterized
as irregularly disseminated, laminated, or massiv. Pyrite clearly predominates in all mentioned textural types,
sphalerite and galena are less frequent, chalcopyrite is only accessory. The ore locally (mainly in central part
of the district) contains relics of original pre-metamorphic structures (collomorphic pyrite, globular
aggregates of sphalerite hosted by galena). The metamorphic recrystallization produced granoblastic textures
with “triple junction” arrangement of sphalerite and (rarely) pyrite. Moreover, synmetamorphic
crystalization of muscovite, albite and Ba-feldspars took place. Post-metamorphic veinlets are the youngest,
they composed of silver minerals (proustite, pyrargyrite, stefanite, Sb-pearceite, native silver), jordanite and
boulangerite, which are accompanied by remobilized common Fe–Pb–Zn sulphides (FOJT et al. 1992). The
metamorphic recrystallization and remobilization of ore is mirrored also in chemical composition of
reprecipitated sulphides: the pyrite contains more Ni, Co and Au, the sphalerites are depleted in Fe and Cd
and the galenas show elevated content of Ag and Sb. The isotope composition of ore lead clusters at the
isochron 0.4 Ga in field between orogenic lead and upper crustal lead.
The gangue is formed mainly by quartz, less calcite, albite, rarely Ba-feldspars, fluorite and cymrite. The
veinlets and lenticular metamorphic segregations contain except calcite also carbonates of dolomite group.
The lens-like barite bodies are concentrated especially in both flanks of the ore zone. The strontium
isotope ratios found in barites (87Sr/86Sr = 0.7065 to 0.7073) are similar to those of the Middle Devonian
seawater. Some parts of fine-grained aggregates of quartz with negligible content of sulphidic minerals are...
Škoda, R., Staněk, J., Čopjakova, R., 2007: Minerálni asociace fosfátových nodulí granitického pegmatitu od Cyrilova u Velkeho Meziříčí, Moldanubikum; čast I-primarní a exsoluční fáze. Acta Mus. Moraviae, Sci. geol., 92, 59.74.
Mineral assemblages of the phosphate nodules from the granitic pegmatite at Cyrilov near Velke Meziříčí, Moldanubicum; part I-primary and exsolution phases.
Granitic pegmatite near Cyrilov, the type locality of cyrilovite belongs to the beryl-columbite-phosphate subtype of the REL-Li type, despite the absence of the beryl. The primary phosphates and associate minerals occur in two assemblages: i) zwieselite nodule minerals . zwieselite, uraninite, ilmenite, ixiolite and Nb-rich ferberite and ii) graftonite nodule minerals . graftonite, sarcopside, wolfeite, triphylite, harrisonite, monazite-(Ce) and xenotime-(Y). The triphylite is completely altered to ferrisicklerite and heterosite. Crystallization of zwieselite decreased the content of F in the melt; this allowed consequent graftonite crystallization. Graftonite crystallized as Li,OH-rich precursor. In the graftonite nodule assemblage, exsolution proceeds in (at least) two stages: i) a Li,OH-rich precursor unmixed to wolfeite, sarcopside I, graftonite II and to the precursor of triphylite and sarcopside II, ii) a further decrease of temperature induces an exsolution of triphylite and sarcopside II from they precursor. The genetic position of harrisonite is not clear. Subhedral monazite-(Ce) associated with wolfeite, graftonite II and sarcopside I and "worm"-like monazite-(Ce) from triphylite-sarcopside II intergrowths is rich in Nd (≤20,35 wt.% Nd2O3) and Sm (≤10,47 wt.% Sm2O3). Based on the chemical composition of primary phosphates and Nb-Ta-Ti-W oxides examined, the assemblage crystallize from Li-poor melt with moderate content of F and low degree of Fe/Mn and Nb/Ta fractionation.
Key words: zwieselite, graftonite, sarcopside, wolfeite, triphylite, harrisonite, ixiolite, Nb-rich ferberite, Nd,Sm-rich monazite-(Ce), granitic pegmatite, Moldanubicum.
Radek Škoda, Renata Čopjakova, Institute of Geological Sciences, Masaryk University, Kotlařská 2, 611 37 Brno, Czech Republic, Czech Geological Survey, e-mail: rskoda@sci.muni.cz, copjakova@sci.muni.cz
Josef Staněk, Institute of Geological Sciences, Masaryk University, Kotlářská 2, 611 37 Brno, Czech Republic
Dokoupilová, P., Sulovský, P. 2007: Minerály skupiny jarositu ze sulfidických paragenezí východní části Českého masivu. Acta. Mus. Moraviae, Sci. geol., 92, 75–91.
Minerals of the jarosite group from sulphide-bearing assemblages on the eastern margin of the Bohemian Massif
The article is devoted to the study of the jarosite group minerals from supergene zone of various sulphidebearing assemblages (polymetalic Pb–Zn ores, pyrite-graphite rocks), emerging in connection with mining activities at the eastern margin of the Bohemian Massif. The most common species on the studied localities were jarosite (K = 0,50–0,88 apfu, Fe3+ = 2,63–3,00 apfu), whereas hydroniumjarosite (H3O = 0,55–0,76 apfu, Fe3+ = 2,82–3,00) and plumbojarosite (Pb2+ = 0,35–0,48 apfu, Fe3+ = 2,64–2,92 apfu) are a less extended. Both Al- and P-bearing jarosites occur in locality Utín near Havlíčkův Brod. The proportions of individual end-members of the jarosite family varies in dependence on the temperature, pH, buffering capacity of the country rocks, and on availability of jarosite-forming elements (K+, Na+, Pb2+, Fe3+, SO42-).
Keywords: jarosite, hydroniumjarosite, plumbojarosite, chemical composition, supergene zone, environment, Bohemian Massif
Pavla Dokoupilová, Institute of Geological Sciences, Masaryk University, Kotlářská 2, 611 37 Brno, e-mail: PavlaDokoupil@seznam.cz
Petr Sulovský, Department of Geology, Palacký University, tř. Svobody 26, 771 46 Olomouc, e-mail: sulovsky@sci.muni.cz
Kocourková, E., Losos, Z., Vávra, V., 2007: Pyromorfit z ložiska olověno-zinkových rud Nová Ves u Rýmařova. Acta Musei Moraviae, Sci. geol., 92, 93–102.
Pyromorphite from Pb–Zn ore deposit at Nová Ves near Rýmařov (Jeseníky Mts., Czech Republic)
Pyromorphite samples from weathering zone of the vein deposit Nová Ves at Rýmařov are identified and studied with respect to their origin. Pyromorphite was found in assemblage with limonite and plumbogumite. Pyromorphihe crystals have zonality, lighter zones (in BSE image) with higher Pb alternate darker zones with higher Ca. Changes in fluids composition and pH during crystallization of pyromorphite are in connection with described zonality. Two independent substitution in pyromorphite were detected: pyromorphite – mimetite (P–As) and pyromorphite – apatite (Pb–Ca). Second type of pyromorphite zonality is represented by changing of compact and porous zones in crystal. It can be in connection with partial dissolution of pyromorphite crystals or with rapid grow stages of crystals. Source of Pb in supergeneous waters (solutions) is galena and source of Ca are vein carbonates, pyrite is primary mineral for traces of As. Phosphorus in water solutions is derived probably from phyllites. The similar situation is described from Zlaté Hory sulphidic deposit.
Key words: pyromorphite, chemical composition, crystal zonality, Pb–Zn deposit, Nová Ves at Rýmařov, Silesicum, Vrbno Unit
Eva Kocourková, Institute of Geological Sciences, Masaryk University, Kotlářská 2, 611 37 Brno, Czech Republic; e-mail: retty@centrum.cz
Zdeněk Losos, Institute of Geological Sciences, Masaryk University, Kotlářská 2, 611 37 Brno, Czech Republic; e-mail: losos@sci.muni.cz
Václav Vávra, Institute of Geological Sciences, Masaryk University, Kotlářská 2, 611 37 Brno, Czech Republic; e-mail: vavra@mail.muni.cz
Jirásek, J., 2007: Nový nález huntitu u Hrubšic na západní Moravě a otázka jeho vzniku. – Acta Mus. Morav., Sci. geol., 92: 103–109.
New find of huntite at Hrubšice, Western Moravia (Czech Republic) and Question of its Genesis
In the Biskoupky serpentinite body (Western Moravia, Czech Republic) an older find of huntite from 1981 was confirmed. The mineral occurs in an active quarry „U Pustého mlýna“ near Hrubšice in the fissures of serpentinite rock in the shallow weathering zone close to present surface. In contrast of its first find huntite forms pseudomorphs after unknown mineral, possibly hydromagnesite. This discovery helps to solve the question of its local genesis. New X-ray powder data and chemical analysis specified data published previously. Its local occurence is compared with other finds from the world.
Key words: huntite, serpentinite, fissure mineralization, genesis, Biskoupky Serpentinite, Hrubšice near Ivančice, Moravia, Czech Republic
Jakub Jirásek, Institut geologického inženýrství, Hornicko-geologická fakulta, Vysoká škola báňská – TU Ostrava, 17. listopadu 15/ 2172, 708 33 Ostrava-Poruba, Czech Republic, e-mail: jakub.jirasek@vsb.cz
Čopjaková, R., Buriánek, D., Škoda, R., Houzar, S., 2007: Turmalinity jižní části svrateckého krystalinika. Acta Mus. Moraviae, Sci. geol., 92, 111.130.
Tourmalinites from the southern part of Svratka Crystalline Complex
Tourmalinites from the southern part of the Svratka Crystalline complex form stratiform layers hosted in mica schist. They probably represent a part of metamorphosed volcano-sedimentary complex primary rich in F and B. Whole rock composition of tourmalinites is close to the surrounding mica schists. P-T conditions 600-630 °C and 5-6 kbar calculated from associated mica schist were interpreted as retrograde metamorphism. Chemical composition of tourmaline strongly varies from high X-site vacant Al-rich schorl to dravite which indicate tourmaline growths over a range of P-T-X conditions. Tourmaline shows three distinct compositional domains (zone I, II, III): chemically inhomogeneous broken core (zone I), volumetrically minor zone II overgrown the core and volumetrically dominant outer zone III, chemically relatively homogeneous. Tourmaline type I correspond to Al-rich schorl with high vacancy and relatively low F (≤0.35 apfu) and it is interpreted as older, low temperature hydrothermal tourmaline. Tourmaline type II is dravite rich in F (≤0.5 apfu) and corresponds to prograde metamorphism. Tourmaline I overgrown by tourmaline II is usually enclosed in other minor minerals (kyanite, muscovite, biotite, garnet). Tourmaline III - Al-rich schorl-dravite formation probably occurred during retrograde metamorphism. Variability of all three tourmaline types is controlled mainly by the substitutions X.YAl WOH XNa-1 Y (Mg,Fe)-1 WF-1 and YFeYMg-1.
Key words: tourmalinite, schorl-dravite, boron, fluorine, metamorphism, mica schist, Svratka Crystalline Complex, Czech Republic.
Renata Čopjakova, Radek Škoda, Institute of Geological Sciences, Masaryk University and Czech Geological Survey, Kotlařska 2, 611 37 Brno, Czech Republic, e-mail: copjakova@sci.muni.cz, rskoda@sci.muni.cz
David Burianek, Czech Geological Survey, Leitnerova 23, Brno, e-mail: Burianek@cgu.cz
Stanislav Houzar, Department of Mineralogy and Petrography, Moravian Museum, Zelny trh 6, 659 37 Brno, e-mail: shouzar@mzm.cz
Opletal, V., Leichmann J., Houzar, S. 2007: Muskovit-plagioklasové polohy v dolomitických mramorech u Prosetína (olešnická skupina, moravikum) – ložní intruze aplitů nebo metaevapority? Acta Musei Moraviae, Sci. geol., 92, 131–142.
Muscovite-plagioclase layers in dolomite marble near Prosetín (Olešnice Unit, Moravicum) concordant injections of aplite or metaevaporites?
Layers of concordant muscovite-plagioclase rock are enclosed in dolomite marble near Prosetín (Olešnice unit, Moravicum). These rocks were previously interpreted as strongly altered injections of silica-poor aplites (oligoclasites). Muscovite-plagioclase rock is white, fine-grained, composed by prevailing oligoclase and small content of muscovite, phlogopite and aggregates of blue tourmaline (dravite). Plagioclase exhibits continuous metamorphic zonation (core An15–28–rim An34–37). Common scapolite (Me41–49) rich in Cl (1.30–2.20 wt. %) do not contain SO3 anion. It forms small nests, containing also phlogopite and zoisite. Mineral assemblages correspond to multiphase regional metamorphism. Part of scapolite is clearly later mineral which replaces plagioclase; albite, chlorite, vermiculite, rare pumpellyite-(Al) and illitesmectite are the youngest retrograde minerals. High Na/K and Mg/Fe ratio and very low content of TiO2 and P2O5 characterise the whole chemical composition of the rock. The studied layers are interpreted as metamorphosed synsedimentary layers of rock compound of carbonate (especially dolomite) and clay with abundant admixture of halite. Similar albite- and/or scapolite-rich rocks (albitite, marialite marbles, dravite-bearing albite-scapolite biotitic gneisses) are developed in whole northern part of Olešnice Unit.
Key words: plagioclase, scapolite, metaevaporites, dolomitic marbles, Olešnice unit, Moravicum, Bohemian Massif.
Vladimír Opletal, Moravské naftové doly a. s. Hodonín, Úprkova 807/6, 675 01 Hodonín.
Jaromír Leichmann, Institute of Geological Sciences, Masaryk University, Kotlářská 2, 611 37 Brno, e-mail: leichman@sci.muni.cz
Stanislav Houzar, Department of Mineralogy and Petrography, Moravian Museum, Zelný trh 6, 659 37 Brno, e-mail: shouzar@mzm.cz
Buriánek, D., Otava, J., 2007: Tři geneticky rozdílné typy granátovců z hlinské zóny a poličského krystalinika – Acta Mus. Moraviae, Sci. geol., 92, 143–150.
Three genetically different types of garnet-rich rocks from Hlinsko Zone and from Polička Crystalline Complex
The garnet-rich rocks are spatially associated with two metamorphosed volcano-sedimetary complexes at the eastern border of the Bohemian Massiv (Polička Crystalline Complex and Hlinsko Zone). The studied rocks represent three genetic types, which are produced by different metamorphic reactions and from chemically different protolites. Garnet-rich rocks from Hlinsko Zone are interpreted as Fe or Fe–Mn rich sediments metamorphosed under medium temperature (about 400–500 °C) and low pressure (below 4 kbar). On the other hand rock from Polička Crystalline Complex represent Fe rich metamorphic rocks (PT condition about 600 °C and 6 kbar) partially modified by metasomatism.
Key words: Hlinsko Zone, Polička Crystalline Complex, garnet-rich rocks, metamorphism
David Buriánek, Jiří Otava, Czech Geological Survey, Leitnerova 22, 658 59, Brno, Czech Republic; e-mail: burianek@cgu.cz; otava@cgu.cz
Abelova, M., 2007: Paleodiet inferred from Ursus spelaeus ROSENMULLER et HEINROTH tooth from Tmava skala cave (Slovak Republic) using carbon isotope analyses . Acta Mus. Moraviae, Sci. geol., 92, 151.156.
Paleodiet inferred from Ursus spelaeus ROSENMULLER et HEINROTH tooth from Tmava skala cave (Slovak Republic) using carbon isotope analyses
Isotopes of carbon were employed in the study of Ursus spelaeus second upper molar M2 from Late Wurm bear cave Tmava skala (Little Carpathians, Slovak Republic). Samples of enamel and dentine were used for the analyses. Variations in the carbon isotope ratio (13C/12C) were used to examine the paleodiet. The δ13C of investigated tooth is -11,8‰ for dentine and -16‰ for enamel. This indicates that the diet of Ursus spelaeus was dominated by C3 biomass. These values suggest a forested habitat.
Key words: Carbon Isotopes, Paleodiet, Teeth, Ursus spelaeus, Upper Pleistocene.
Institute of Geological Sciences, Faculty of Science, Masaryk University, Kotla.ska Street 2, Brno 611 37, Czech Republic. abelova.m@mail.muni.cz
Roszková, A. 2007: Palynologie vybraných kvartérních lokalit (Stříbrná bystřina, Rýchory) Krkonošského národního parku. – Acta Mus. Moraviae, Sci. geol., 92, 157–168.
The pollen analysis of the chosen Quaternary localities (Stříbrná bystřina, Rýchory) from the Giant mountains
The paleobotanical reconstruction of the vegetation development of the Giant Mountains is based on the pollen analysis of sediment of moors. The peat has risen and accumulated the pollen grains and spores from the Late Glacial during the Holocene. The peat profiles studied were taken from two localities (Stříbrná bystřina, Rýchory) differing in vegetation types and topography. The investigated material was composed by peat mossy sediment with small admixture of mineral substratum. The both cores (70 cm) were sampled at intervals of 5 or 10 cm in 1–3 cm3. Pollen frequency was very good in all samples except samples from 10 cm. The results of the pollen analysis were illustrated in pollen diagrams compiled by the special program POLPAL. The Subboreal, the Older and Younger Subatlantic have been determined (4500 BC – to date) in Stříbrná bystřina locality and the Older and Younger Subatlantic have been determined (800 BC – to date) in Rýchory locality.
Key words: Pollen analysis, The Giant Mountains, Holocene, peat – bog.
Alena Roszková, Institute of Geological Sciences, Faculty of Science, Masaryk Univerzity, Kotlářská 2, 611
37, Brno, Czech republic, e-mail: 64038@mail.muni.cz