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The Dębowiecki conglomerate is a coarse-grained Miocene sediment, which occurs in the western part of the Carpathian Foredeep between Cieszyn, Jastrzębie and Bielsko (Poland). This unit includes varigrained conglomerates and coarse-grained sandstones. The thickness of the unit may reach up to 260 m. The Dębowiecki conglomerate was mentioned for the first time by Petrascheck (see Konior 1965). However, Tołwiński (1950) described this conglomerate in detail and placed it into the so-called "debowiecki layers". This research aims to determine the composition and origin of the Dębowiecki conglomerate's clastic material. At current stage, 22 samples from the Dębowiecki IG 1 borehole were selected. The fraction larger than 2 mm was used for the petrographic analysis. Four petrographic groups were distinguished among the clastic material. Mudstones, sandstones, fragments of carbonates and crystalline rocks have been identified. Mudstone pebbles form the largest group, amounting to 23-57%. They are represented by gray, gray-brown to black rocks. Pebbles characterized by high cohesiveness dominate. Sharpedged and subrounded clasts are predominant, which may indicate a short transport of the material from the source area. Gray, very concise mudstone pebbles with poorly encased grains are very similar to the Carboniferous mudstones which can be found south-west from Dębowiec. It can therefore be assumed that a large part of the material comes from direct substratum of the Dębowiecki conglomerate made of productive Carboniferous, namely the Poręba beds, which are included to the paralic series. The Poręba Beds (Namurian A) occur within the Upper Silesian Coal Basin (Kotas & Malczyk 1972). The sandstones are represented by numerous petrographic varieties (3-24%). The light-grey, with a tinge of brown sandstones, with silica or silty-silicate cement maybe of productive Carboniferous origin. The light-green, fine-grained sandstones with glauconite resemble flysch deposits. The dark-grey sandstones may be of Culm origin. The white-yellow, white or beige limestone clasts (0-11%) indicate the similarity to the Devonian carbonates known from the Śląsk Cieszyński basement. Some of them have also strong affinity with the carbonate exotics from the Carpathians. Among magmatic rocks (0-6%), the granitoids are prevailing. They may come from the flysch deposits, or from the Cieszyn Ridge.
W pracy przedstawiono wyniki badań laboratoryjnych mechanicznego zachowania się sześciu rodzajów skał przy dynamicznych obciążeniach. Do badań wybrano piaskowce i mułowce z utworów karbońskich towarzyszących pokładom węgla kamiennego w Górnośląskim Zagłębiu Węglowym, dolomity i piaskowce szare ze złoża rud miedzi w Legnicko-Głogowskim Okręgu Miedziowym oraz wapienie i piaskowce z utworów triasowych ze złoża wód termalnych w niecce podhalańskiej. W pierwszej kolejności przeprowadzono badania podstawowych parametrów fizyczno-mechanicznych, a następnie wyznaczono parametry amplitudowo-czasowej charakterystyki deformacji próbek skalnych obciążonych dynamicznie. Ustalono zdolność badanych skat do dylatancji przy nierównomierności obciążenia dzeta = sigma3/sigma-1 <0,2...03. Przedstawiono ogólne prawidłowości rozwoju dylatancji i określono podstawowe deformacyjne właściwości skał jako ośrodków dylatancyjnych. Przeprowadzono analizę zmiany energii procesów deformacji w warunkach osłabienia dylatancyjnego. Sformułowano podstawowe zależności matematyczne do oceny energochłonności procesów deformacyjnych. Wyznaczono akustyczne właściwości skał oraz podano sposób sejsmicznego rozpoznania rozwoju procesu dylatancji. Przytoczono przykłady praktycznego wykorzystania zjawiska dylatancji w górnictwie.
This article presents the results of laboratory tests on the mechanical behavior of six types of rock under high dynamic loads. Selected for testing were sandstones and siltstones of Carboniferous formations associated with coal strata in the Upper Silesian Basin, dolomites and sandstones from copper ore deposits in the Legnica-Głogów Copper District, and Triassic limestones and sandstones from the deposits of thermal waters in the Podhale syncline. An examination was carried out on the basic physical and mechanical parameters, and then the parameters of the amplitude-time characteristics of the rock samples loaded dynamically. The study investigated the tendency of rocks to dilatancy under an uneven load dzeta = sigma3/sigma-1 <0.2...0.3. The overall principles of dilatancy development have been presented and the basic deformation properties of rocks as a dilatancy medium have been defined. The energy of deformation processes in conditions of dilatancy weakening has been analyzed. The basic mathematical relations for the evaluation of energy consumption of deformation processes have been formulated. Acoustic properties of rocks have been determined and a way to recognize the development process of dilatancy with the help of the seismic method has been shown. Examples of the practical use of the phenomenon of dilatancy in mining have been presented.
We report the first occurrence of diagenetic or low grade metamorphic monazite from the Palaeozoic mudrock successions of the Kaczawa Complex of the West Sudetes, Poland. Where observed in relation to the enclosing mudrock, this monazite comprises tiny irregular grains, less than 20 microns in diameter, intergrown with the surrounding matrix minerals. This monazite resembles previously described examples of diagenetic monazite from elsewhere in the world in mostly possessing low contents of Th and U but differs in forming much smaller grains, which show only slight zonation of rare earth elements (REEs). Some of the monazite grains studied also appear to have formed synchronously with the cleavage, perhaps a function of early deformation and fluid release in an accretionary prism environment. Relatively Th-rich cores, and an association with altered detrital biotite in some instances, suggests that at least some of the in situ monazite growth might have taken place as overgrowths on primary detrital monazite particles.
Taxonomic studies of Cretaceous inoceramid bivalves are confounded by high levels of intraspecific morphological variation within the group. Such variation is illustrated here using Cremnoceramus bicorrugatus s.s. (Marwick, 1926) from the lower Coniacian of New Zeland. This taxon displays a remarkable range of intraspecific variation that is the sum of three major components: 1) a basic set of ontogenetic transformations between the juvenile, immature and adult stages; 2) intra-populational variation in the relative timing or rate of developmental events; and 3) intra-populational variation in therate of absolute growth. The first of these components was largely genetically determined, whereas the other two were probably influenced by extrinsic environmental factors. Taxonomic interpretation of C. bicorrugatus s. s. is not possible without some understanding of both the basic ontogenetic plan and developmental variations within that plan. Interpretation is facilitated by the profound and step-wise nature of the ontogenetic transformations. In many other inoceramids, however, ontogenetic transformations are more subtle but may be subject to equally significant intraspecific developmental variations. Therefore, inoceramid taxonomists should describe not only total population variation, but also should document ontogenetic development in any species. In this way it is possible to identify basic ontogenetic plans, constrain likely limits to intraspecific variation, and distinguish intraspecific from interspecific morphological variation.
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