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Sandstones and conglomerates Peruc Mbrs (lower Cenomanian , Upper Cretaceous ) of eastern Bohemia and coal mass in them
Martinec, Petr ; Kubina, Lukáš ; Rojáková, T.
A reasonably complete knowledge of the development of East Bohemia’s Lower Cenomanian sediments (Peruc Mbr) is still lacking. The sediments originate from rivers flowing from the buried Hořice-Nové Město elevation to Moravia in the SE direction, via a flatland depression. The sandstone and conglomerate bodies within the Litice Chlum area under investigation are channel river sediments accompanied by sedimentation in river lakes or oxbow lakes. The landscape of the region showed the character of a low-relief peneplain. At Sopotnice site, the surface of Litice kaolinite massif of granodiorite with a weathered crust incorporates fine-grained conglomerates with white quartz and quartzite pebbles in a sandy matrix. They form wedge-shaped channel bodies of several dozens centimeters thickness. The textures are massive, with inconspicuous positive gradation bedding of medium to poor bed sorting. By their character they correspond to the fill of an instable riverbed that kept changing its position in the flatlands. In the matrix, kaolinite dominates over illite.
Fulltext: content.csg -  DOC
Plný tet: UGN_0398209 - DOC
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Coal tonsteins and K- bentonite ( tuffs ) in Poruba Mbrs, Ostrava Formation in the Czech part of the Upper Silesian Basin ( Namur , Arnsberg )
Martinec, Petr ; Horák, J.
The Poruba Mbrs (Arnsbergian, Namurian A) constitute the topmost stratum of Ostrava Fm (Mississippian: Pendleian – Arnsbergian, Namurian A). The Poruba Mbrs incorporate sequences of terrigenous sediments (K-bentonites and coal tonsteins) where a total of 13 isochronous horizons were found: they extend over larger or smaller areas and exhibit a close spatial relationship to the other faunistic horizons or coal seams located there. The horizons, which are of volcanic origin, were formed by deep transformation of acidic volcanic ash under conditions of tropical climate, either in coal tonstein environments or in terrigenous environments (K-bentonites) in absence of humine substances. The petrographic type of the volcanic ash precursor can be interpreted within the context of the discrimination diagram of Zr/TiO2 vs. Nb/Y (FLOYD & WINCHESTER, 1977). The coal tonsteins and the K-bentonites correspond to the same type of volcanic material for which the points of projection of chemical analyses fall within the field bounded by rhyodacite to dacite, near the boundary with the andesite field.
Fulltext: content.csg - DOC
Plný tet: UGN_0398207 - DOC
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Poruba Mbrs, Ostrava Formation ( Namurian A, Arnsberg ) in the Czech part of the Upper Silesian Basin
Horák, J. ; Martinec, Petr ; Hoch, I.
In the Czech part of the Upper Silesian basin, full preservation of the Poruba Mbrs of Ostrava Fm, i.e., retention of their full thickness, can be observed only in the eastern and southern zones of the basin, while no more than relics exposed by denudation remain in the western and central zones. The Poruba Mbrs (Namurian A, Arnsbergian, E2b) were deposited on the outskirts of Ostrava Fm (Namurian A, Pendleian-Arnsbergian) on a flat coastal plain, interspersed with infrequent but regularly spaced marine transgressions. Individual sedimentary sections—mezocycles—are well-defined (within the meaning of the concept put forward by ČEPEK & HAVLENA 1975). Their sedimentary development reflecting the climate changes during the Carboniferous period have been described. Five complete mezocycles were identified (named Koks, Konrad, Lotar, Otakar, and Gaebler after major marine horizons), plus an incomplete one (Filip, constituted by only the upper continental portion of the mezocycle), inasmuch as the marine part (a group of faunistic horizons of Barbora) is presently ascribed to Jaklovec Mbr.
Fulltext: content.csg - DOC
Plný tet: UGN_0398206 - DOC
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Czech and Polish Conference Geology of Coal Basins /9./
Kožušníková, Alena ; Ruppenthalová, Lucie
Department of Laboratory Research on Geomaterials of the Institute of Geonics AS CR has organized the Czech - Polish conference about geology of coal basins since 1993. Traditionally, at the conference meet experts especially from the Czech Republic and Poland, dealing with the development and research of coal deposits, geology of the coal basins, tectonics and coal petrography. However, with new trends in the use of coal deposits, there are also presented the results of research in physical and chemical properties of coal and coal mass, pyrolysis and combustion processes or geosequestration of CO2 into coal seams.
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Project monitoring the stress-strain state of the rock mass during extraction of coal seam 30 (634) within the test run mining methods corridor - a pillar in the OPJ Mine CSM - Sever. Proposal verify the possibility to use anti-shake prognosis and prevention using mining methods corridor - pillar within pilot operation in seam 30 (634) in OPJ Mine CSM - Sever
Waclawik, Petr ; Koníček, Petr ; Ptáček, Jiří ; Šňupárek, Richard ; Kajzar, Vlastimil ; Kukutsch, Radovan ; Vavro, Martin ; Souček, Kamil ; Holečko, J. ; Stoniš, M. ; Suchanek, E. ; Sojka, R. ; Przeczek, A.
On the basis of a contract for No. 850/33/10 and Appendix 1 of this contract , between OKD , as, ČSM and the Institute of Geonics AS CR, v.v.i. we present the following project monitoring stress tension-deformation condition of the rock mass during extraction of coal seam No.30 (634 ) within the test run mining methods corridor - pillar in a protective pillars jam CSM Mine, north location. Monitoring of the stress tension-deformation state of rock mass is a prerequisite for successful verification of a new mining method unapproved hall - pillar and its further use in the Czech part of the Upper Silesian Coal Basin. This mining method is designed on the basis of experiences and practices, which are verified in different natural conditions and depths, and therefore it is necessary for the verification of the conditions of the Czech part of the Upper Silesian Basin on the basis of the proposed geotechnical monitoring. Test operation of the new hall - pillar method will be implemented in the seam No.30 (634 ) in the rock mass included in the category without the risk of shocks.
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Thermal behaviour of organically modified clays
Plevová, Eva ; Vaculíková, Lenka ; Vítámvásová, E. ; Šugárková, Věra ; Martynková, G.S.
The clay minerals were modified by two alkylammonium cations under sorption procedure. T X-ray powder diffraction and FT-IR spectroscopy were used to evaluate the intercalation process of organic cations int the clay structure. The organo - montmorillonites exhibited IR spectra giving evidence about sorption or intercalation of the alkylammonium cations. The enhancement of the basal spacing obtained by X-ray diffraction confirmed the intercalation process of cations into montmorillonite and vermiculite samples. Thermal behaviour of the modified clay minerals was investigated by simultaneous thermogravimetry and differential thermal analysis. The organically modified montmorillonites exhibited the higher values of temperatures related to the total melting. Also the temperatures of exotherm effects connected to recrystallization and transformation increased with the concentration of alkylammonium salts. The temperatures of dehydratation and dehydroxilation decreased with concentration of alkylammonium cations. Vermilulite samples showed generally reducing of their thermal stability.
Fulltext: content.csg -  PDF
Plný tet: UGN-0393204 - PDF
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Effects of water jet on heat-affected concretes - laboratory tests
Klich, Jiří ; Sitek, Libor ; Zeleňák, Michal ; Hlaváček, Petr ; Foldyna, Josef ; Bodnárová, L. ; Válek, J.
The paper is dealing with the effects of flat high-speed water jet on concretes affected by high temperature. Research should help to correct use of water jet technology in repair works on concrete structures especially after wildfires in tunnels, underground garages, etc., which are exposed to enormous thermal stress.
Fulltext: content.csg - PDF
Plný tet: UGN_0392712 - PDF
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Design of roadway support in coal mines
Šňupárek, Richard
Design of roadway support in coal mines is mostly based on simple united methods for designating of support loading and for design of support constructions. These methods are based in majority of cases on practical engineering processes with using of empirical knowledge from the area of interest (mine, deposit, stratigrafic unit). In cases with similar conditions it is possible to compare the methods of roadway support design. The contribution deals with comparison of design methods used in Ostrava Karviná coal basin and Ruhr coal basin in Germany.
Fulltext: content.csg - DOC
Plný tet: UGN_0383911 - DOC
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