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Provenance of Albian to Cenomanian exotics-bearing turbidites in the Western Carpathians : a heavy mineral analysis

Aubrecht Roman, Bellová Simona, Mikuš Tomáš

Geological Quarterly

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2020

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Vol. 64, No. 3

658--680

EN

Throughout the Cretaceous, Tethyan oceanic branches gradually closed, and various ophiolites became obducted and eroded. Their remnants, however, provide an abundance of exotic clasts of unknown origin. Sandstone samples from the oldest, Albian exotics-bearing strata of the Pieniny Klippen Belt and Central Western Carpathians were analysed for heavy minerals. These samples were dominated by a high content of chrome-spinels, zircon, tourmaline, apatite and rutile. Titanite, kyanite, monazite, epidote, sillimanite and staurolite were much less abundant. Garnet was generally also rare; however, it was locally common, as were blue amphiboles, pyroxenes and kyanite. The spinels found in the samples were predominantly derived from harzburgites (supra-subduction peridotites and volcanic rocks). The blue amphiboles represented glaucophanes to ferroglaucophanes, and were derived from HP/LT metabasites. Pyroxenes (enstatite, less commonly augite and diopside) most likely came from coeval volcanics. Most of the tourmalines were derived from metasedimentary rocks and locally from granitoids. Furthermore, some have a complex zonation with two phases of tourmaline, or tourmaline intergrown with quartz. These were likely derived from ophiolitic sources. The results from our analysis indicate a dominance of ophiolites and older sediments with local input of continental crust metamorphic rocks. A resulting palaeogeographic reconstruction involves secondary doubling of the Neotethys suture zone and its lateral shift north of the Central Western Carpathians, which formed a common source for exotics in the Pieniny Klippen Belt and the Central Western Carpathians.

2

Otrzymywanie tworzywa szkło-krystalicznego z fazą ZnAl2O4 w wyniku eliminacji struktur piroksenowych

Okupski T., Herman D., Walkowiak W.

Materiały Ceramiczne

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2011

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T. 63, nr 2

379-385

PL

W artykule przedstawiono wyniki badań nad możliwością zastosowania tworzywa szkło-krystalicznego z układu CaO-MgO-ZnO-Al2O3-B2O3-SiO2, będącego modyfikacją układu CaO-MgO-Al2O3-SiO2, jako spoiwa do ziaren ściernych z mikrokrystalicznego tlenku glinu typu SG. W wyniku zmiany składu chemicznego tworzywa z układu Al0,54B0,9Mg0,05Zn0,38Ca0,12Si0,51O3 możliwa jest eliminacja podstawowych struktur krystalicznych z grupy krzemianów (diopsyd, augit) na korzyść fazy spinelowej (ZnAl2O4). Tworzywo szkło-krystaliczne z udziałem gahnitu oraz należącego do grupy krzemianów wyspowych wilemitu (Zn2SiO4), charakteryzuje się korzystniejszymi właściwościami mechanicznymi (KIc = 2,04 MPaźm1/2) w porównaniu do tworzyw z udziałem faz krzemianowych (KIc = 1,28 MPaźm1/2).

EN

The paper presents an attempt of application of glass-crystalline material, coming from the CaO-MgO-ZnO-Al2O3-B2O3-SiO2 system and being a modification of the CaO-MgO-Al2O3-SiO2 system, as a binder for abrasive grains of microcrystalline alumina of the SG type. The results indicate that a change of the chemical composition can eliminate crystal phases from a silicate group (diopside, augite) in the spinel phase (ZnAl2O4) favour. The glass-ceramic material containing crystal phases of gahnite (ZnAl2O4) and willemite (Zn2SiO4) has better mechanical properties (KIc = 2.04 MPaźm1/2) in comparison to the materials with the pyroxene phases (KIc = 1.28 MPaźm1/2).

3

Obiekty przyrody nieożywionej wyspy Teneryfa

Stanienda K., Wasilczyk A.

Górnictwo i Geologia

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2011

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T. 6, z. 4

113-127

PL

W artykule zaprezentowano obiekty przyrody nieożywionej, typowe dla wyspy Teneryfa. Opisano skały występujące w obszarze Parku Narodowego Teide, w tym samego wulkanu Teide, a ponadto utwory odsłaniające się w obszarach Montana de Chinyero, Puerto de Santiago, Masca, Los Gigantes i Garachico. W obszarze Teneryfy dominują lawy, bazalty z widocznymi kryształami oliwinu, fonolity i skały maficzne. Można tu również spotkać trachity i andezyty, a na małych plażach czarny piasek wulkaniczny, zawierający pirokseny, oliwiny, skalenie oraz minerały żelaza (magnetyt).

EN

The objects of inanimate nature, typical for Tenerife Island were presented in this article. Rocks of the National Teide Park, including Teide Volcano, moreover rocks from outputs of Montana de Chinyero, Puerto de Santiago, Masca, Los Gigantes and Garachico were described there. Lavas, basalts with visible olivine Crystals, phonolites, and maphic rocks dominate in the area of Tenerife Island. Moreover it is possible to find there trachytes and andesites and on the beaches, black, volcanic sand with pyroxenes, olivines, feldspars and iron minerals (magnetite).

4

The temperature - and stress fields of valves of IC engine

Jaskólski J., Krzyżak R.

Journal of KONES

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2007

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Vol. 14, No. 3

245-252

EN

The paper concerns building up one exhaust valve of composite-steel and two intake ceramics-steel valves of a hypothetical adiabatic engine. The input temperatures were computed using three diverse FORTRAN95 programs, solving a shortened optical integral equation with radiative transfer, transient differential equation while starting and switching off the engine and a rod like diff. Equation with 'progonka' (Thomas) solution. The ANSYS11 programme was fed up with the output of the programs. It turns out that, generally, a mineralogical, crystal-chemical approach to the joining of materials results in stresses known from the common metal engines. Such problems as CTE enhancing (partly hypothetical) by means of doping the anionic compounds by cationic ones, swelling of structures, compressibility versus coefficient of thermal expansion (CTE) , compatibility of crystal motifs while joining, thermal shock resistance, switching the bonds, mechanical longevity, radiation protection etc were addressed. It turns out that true nature of the temperature and stress field, especially of the exhaust valve is closer to the FORTRAN temperature computation than, e.g. From the heat film coefficients (ANSYS11).

5

Comparative Mössbauer studies of the Baszkówka ordinary chondriteand some other meteorites

Gałązka-Friedman J., Bauminger E. R., Nowik I., Bakun-Czubarow N., Stępniewski M., Siemiątkowski J.

Geological Quarterly

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2001

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Vol. 45, No 3

319-326

EN

It was suggested that perhaps Mössbauer parameters of troilite could serve as a criterion for an interpretation of the origin of various meteorites. It was found that in three meteorites coming from the same parent body (Baszkówka, Mt. Tazerzait and Songyuan) the angle between the principal axis of the electric field gradient (EFG) and the direction of the magnetic field in troilite is around 60o. Further investigations showed that in some other meteorites, not belonging to this group, this angle is close to 90o.

6

Phosphate and silicate inclusions in apatite and pyroxene from the Precambrian nelsonite and jotunite of NE Poland

Kozłowska A., Wiszniewska J.

Archiwum Mineralogiczne

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2001

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T. 54

5-21

EN

Melt inclusions were investigated in apatite from nelsonite from the Suwałki anor-thosite massif and in pyroxene from the Fe–Ti–P-rich monzodiorite (jotunite) from the Sejny massif, both of Proterozoic age and occurring within the ranges of the Mazury crystalline complex in NE Poland. The melt inclusions in apatite were filled by an agg-regate of pyroxene, apatite, calcite, plagioclase, biotite, halite, sylvite, ore mineral plus aqueous solution and gas bubble. At 880oC in the inclusions two melts: silicate and phosphate one, were observed which neither homogenized nor changed their propor-tions up to 1080oC. This indicated the formation of nelsonite from the melt composed of two immiscible phases. Inclusions in pyroxene from jotunite were filled by pyroxene, feldspar, apatite, carbonate and ore mineral with gas bubble. Their homogenization tem-peratures were from 1090 to 1180oC; at 1000 to 1030oC in silicate melt small droplets of carbonate and phosphate melt were visible, homogenizing subsequently in one melt phase. The behaviour of the two melts in the studied inclusions may indicate a genetic affinity of nelsonite with monzodioritic rocks.