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EN
The Cambrian Explosion is one of the profound evolutionary events in the history of life on Earth when diverse animal phyla burst into existence almost from nowhere. However, despite this sudden appearance, the fossil record and evolutionary history of animals goes much deeper in time into the Neoproterozoic. This contribution reviews the earliest known faunas, their diversity and ecological complexity. Moreover, specimens of Ediacaran biota from the Polish museum collections are briefly presented.
EN
The paper presents results of new petrographic and mineralogical analyses of Ediacaran clastic rocksin the Bibiela PIG-1 borehole drilled in 2016. Three types of microlithofacies have been distinguished. The basic types of rocks are siltstones and claystones containing thin layers of mudstones. Breccia is common, while sandstones form thin packages. The Ediacaran rocks are cut by numerous veins that intersect each other. They are filled with carbonates, quartz, chlorites and kaolinite. Ankerite, Fe-dolomite, dolomite, Mg-siderite (sideroplesite, pistomesite, metisite), Mn-siderite (manganosiderite) and Fe/Mn-calcite were identified among the carbonate minerals. Vitrinite reflectance index Ro (1.68%), Kübler index KI (0.72 to 1.10 Δo2ϴ CuK2) and smectite content (10-25%) in the mixed-layer illite/smectite indicate that the Ediacaran rocks in the Bibiela PIG-1 borehole have been altered under the conditions of late diagenesis at the maximum temperature estimated at approx. 160oC
EN
In the northern part of the Upper Silesian Block, there is a latitudinal structure, several kilometres wide, stretching from Zawiercie through Siewierz towards Tworóg, where Devonian carbonate formations occur directly under the Triassic overburden. This tectonically controlled elevated structure, redefined in this paper as the Brudzowice (Siewierz) elevation, is the effect of Variscan restructuring of the area, which was accompanied by magmatism carrying polymetallic mineralization, and by intense erosion reaching the Lower Devonian formations. The Bibiela PIG-1 borehole, drilled in 2016, revealed the presence of Ordovician and Ediacaran clastics under the Devonian, in which metasomatic changes and ore mineralization located within the range of low-temperature hydrothermal effects associated with an acid magmatic intrusion were observed. A complex ore association with Cu, Fe, Zn, Pb, and Ni and As minerals have been found. The presence of chalcopyrite extends the list of documented manifestations of copper mineralization in the Upper Silesian Block, so far observed in the late Paleozoic and Lower Triassic formations, thus indicating the prospect for further exploration in this area.
EN
Borehole Cianowice-2 was drilled several kilometers to the NW of Kraków. Under the Jurassic deposits, at a depth of 265.3-600.0 m, Ediacaran clastic sediments with polymetallic mineralization represented by a group of dozen ore minerals, mainly sulphides and sulphosalts were found. This is low-temperature, hydrothermal mineralization, which along with local metasomatic transformations indicates that the Ediacaran rocks are probably related to the nearby intrusion of acid igneous rocks. In order to locate this hypothetical intrusion, detailed gravimetric and magnetic tests were performed. As a result, a negative gravimetric anomaly was discovered with minima in the region of Maszyce and Pr¹dnik Ojcowski. An optimal borehole location for a further exploration was proposed near the Podmaszyckie hamlet at a depth of about 1000 m.
EN
A set of geological maps and geological cross-sections was prepared to document the geological setting of sedimentary basins developed on the western slope of the EEC and adjacent areas to the west. On the basis of these data and literature on the subject, the evolution of the sedimentary basins in the study area was reviewed, with special emphasis on the Ediacaran–Lower Palaeozoic basin. The basin originated during late Ediacaran rifting, related to the latest stages of breakup of the Precambrian super-continent Rodinia/Pannotia, associated with large-scale igneous activity. The rifting ultimately led to the formation of the Tornquist Ocean and subsequently, during the latest Ediacaran to Middle Ordovician, the SW margin of the newly formed Baltica became a passive continental margin. The upper Cambrian depocentre in the Biłgoraj-Narol Zone and the Łysogóry Block tentatively is interpreted as a small, narrow foredeep, related to the docking of the Małopolska Block to the western margin of Baltica. From the Late Ordovician through the Silurian, a gradual change to a collisional tectonic setting is observed across the entire SW margin of Baltica, as well as in the zones adjacent to it from the west, which together became the site of development of the extensive Caledonian foredeep basin, related to the convergence and collision of Avalonia and Baltica. The oblique character of the collision resulted in a prominent diachronism in the development of the foredeep basin. This refers to the initiation of basin subsidence, the starved basin phase, the main phase of rapid subsidence and supply of detritus from the west, and the termination of basin development. The Early Mississippian (Bretonian) phase of uplift and erosion and, to a lesser degree, also the Late Pennsylvanian one significantly affected the structure of the western EEC. During the Mississippian, extensive magmatic activity took place at the SW margin of East European Craton, in the region referred to here as the Baltic-Lublin Igneous Province.
PL
Okruszcowanie w skałach ediakaru w otworze wiertniczym Cianowice 2 jest bardzo ubogie. Dość bogaty jest jednak zespół mineralny reprezentowany przez: chalkopiryt, piryt, piryt framboidalny, bornit, minerały szeregu galena–clausthalit, minerały szeregu tennantyt– tetraedryt, kowelin, chalkozyn, wittichenit, markasyt, sfaleryt, anglezyt oraz minerały ziem rzadkich (calcioancylite-(Ce), bastnäsyt). Stwierdzona mineralizacja ma wyraźnie charakter hydrotermalny, niskotemperaturowy, a w okruszcowaniu znaczącą rolę odgrywa piryt framboidalny. Natomiast w utworach kambru w otworze Trojanowice 2 występuje okruszcowanie o charakterze śladowym. Stwierdzono tu ubogi zespół minerałów kruszcowych reprezentowany przez piryt (głównie framboidalny) i chalkopiryt. To okruszcowanie jest prawdopodobnie również w znacznej części epigenetyczne. W młodszych utworach obydwu otworów wiertniczych (dewon dolny i środkowy, jura dolna i środkowa) dominują siarczki żelaza – piryt i markasyt, lokalnie występuje wtórny getyt i limonit. We wszystkich osadach klastycznych powszechnie występują tlenki tytanu i tytanit. W otworze Trojanowice 2 w skałach węglanowych jury górnej zaobserwowano niewielkiej miąższości brekcje tektoniczne z pirytem i markasytem w spoiwie oraz z impregnacjami skały otaczającej drobnokrystalicznym pirytem.
EN
Ore mineralization in Ediacaran rocks from the Cianowice 2 borehole is very poor, but despite that, the mineral association is quite variable and represented by framboidal pyrite, chalcopyrite, pyrite, bornite, galena-clausthalite, tennantite-tetrahedrite, covellite, chalcocite, wittichenite, marcasite, sphalerite, anglesite and two rare earth elements minerals (calcioancylite-(Ce), bastnäsite). The mineralization is of low temperature and hydrothermal nature. Cambrian sediments in the Trojanowice 2 borehole contain only traces of mineralization. The poor assemblage of ore minerals is represented by pyrite (mainly framboids) and chalcopyrite. Most of this mineralization is probably epigenetic in origin. In the younger sediments drilled by both boreholes (Lower and Mid-Devonian, Lower and Mid-Jurassic) iron sulphides (pyrite and marcasite) predominate, and locally secondary goethite and limonite can be found. In all the clastic sediments titanium oxides and titanite are common. In the Trojanowice 2 borehole in the Upper Jurassic carbonates contain thin tectonic breccias with pyrite and marcasite in the cement as well as fine-grained pyrite impregnation in the hosting rocks.
PL
W artykule przedstawiono charakterystykę najstarszych zespołow mikroskamieniałości organicznych, udokumentowanych w dwóch nowych otworach wiertniczych (Trojanowice 2 i Cianowice 2) zlokalizowanych po przeciwnych stronach strefy uskokowej Krakow–Lubliniec oddzielającej blok gornośląski i małopolski. Wiercenia te są oddalone od siebie o około 6 km. Przeprowadzone badania palinologiczne pozwoliły na oznaczenie wieku utworów klastycznych nawierconych pod utworami dewonu dolnego w otworze wiertniczym Trojanowice 2 i pod utworami jury dolnej w otworze Cianowice 2. Najstarsze asocjacje mikroskamieniałości organicznych, korelowane z poźnoediakarskimi utworami fliszowymi bloku małopolskiego, udokumentowano w ponad 330-metrowym odcinku profilu Cianowice 2. W najniższej, 44,5-metrowej części profilu Trojanowice 2 występują zespoły mikroskamieniałości organicznych podobne do opisanych z utworów najstarszego kambru, reprezentujących formację z Borzęty, w krawędziowej wschodniej cześci bloku górnośląskiego. W skład udokumentowanych asocjacji mikroskamieniałości organicznych wchodzą najstarsi przedstawiciele świata bakterii, glonów, grzybów, a także zwierząt.
EN
The paper presents the characteristics of the oldest groups of organic microfossils found in two new boreholes (Trojanowice 2 and Cianowice 2) located on the opposite sides of the Krakow–Lubliniec fault zone separating the Upper Silesian and Małopolska blocks. Detailed palynological research allowed determining the age of clastic sediments drilled under the Jurassic and Devonian. Two characteristic microfossil assemblages have been documented: the Late Ediacaran assemblage dating the age of the Małopolska Block basement, and the Terreneuvian assemblage, known from the oldest Cambrian sediments of the Upper Silesian Block. The se associations of organic microfossils include the oldest representatives of bacteria, algae, fungi and animals.
PL
W artykule zaprezentowano sformalizowany schemat podziału litostratygraficznego utworów klastycznych i wulkanogenicznych ediakaru, wypełniających lubelsko-podlaski basen sedymentacyjny, zlokalizowany we wschodniej i południowo-wschodniej Polsce. W sukcesji górnego ediakaru wyróżniono osiem jednostek litostratygraficznych, w tym siedem formacji i jedno ogniwo. Podstawą wydzielenia jednostek było zróżnicowanie makroskopowych cech litologicznych w profilach z ediakaru. W charakterystyce jednostek litostratygraficznych zawarto historię ich nazewnictwa, kryteria zdefiniowania jednostki, opis, stratotypy i hipostratotypy, granice, chronostratygrafię, skamieniałości, interpretację genetyczną, miąższość, rozprzestrzenienie regionalne i odpowiedniki litostratygraficzne na obszarach sąsiednich.
EN
The paper presents a formalized lithostratigraphic scheme of the Ediacaran clastic and volcanogenic deposits from the Lublin-Podlasie sedimentary basin, located in eastern and south-eastern Poland. The upper Ediacaran succession consists of eight lithostratigraphic units, including seven in the rank of formation, and one member. The basis for the identification of the units was the variability of macroscopic lithological features in the Ediacaran sections. The characterization of the lithostratigraphic units provides the history of their names and criteria for defining the units, and their description. The stratotypes and hypostratotypes, boundaries, chronostratigraphy, fossils, interpretation of origin, thicknesses, regional distribution patterns and lithostratigraphic equivalents from neighbouring areas are also characterized.
EN
The results of palynological investigations of the oldest siliciclastic strata recognized in the Małopolska Block, situated in southeastern Poland, within the Trans-European Suture Zone (TESZ), are summarized in this paper. Siliciclastic flysch-type rocks without macrofossils have been encountered in over 1000 boreholes within the Małopolska Block, below Paleozoic, Mesozoic, and Cenozoic deposits of various ages (from Ordovician up Miocene). The lithostratigraphy of the pre-Ordovician basement in the Małopolska Block is not fully known. Thin tuffs or tuffites layers have been found in many sections of these rocks. In some of the boreholes (e.g., Książ Wielki IG 1), a late Ediacaran age has been determined for a tuffite interlayer of the rocks underlying Ordovician strata, by U-Pb dating of zircons recovered from that tuffite, that indicated 549 š3 Ma. This article describes the palynology of samples from twelve selected profiles which contained recognizable organic microfossils, in various states of preservation. The associations recovered are dominated by small spherical forms, without any ornamentation, belonging to the Leiosphaeridia, and by fossil cyanobacteria represented by straight or coiled thread-like fragmentary specimens. Similar organic microfossil associations, with poorly differentiated species and genera, are known from many late Ediacaran occurrences.
PL
W wyniku aktualnie przeprowadzonych przez Państwowy Instytut Geologiczny badań materiału rdzeniowego z archiwalnego wiercenia DB-4 z rejonu Doliny Będkowskiej (południowa część bloku małopolskiego) udokumentowano występowanie złota w szarozielonych i brunatnych metasedymentach ediakaru. Podwyższone zawartości złota (maks. do 15 ppm) stwierdzono w próbkach punktowych kilku interwałów głębokościowych, przede wszystkim z głębokości 253,0 i 584,5 m. W strefach tych występują liczne żyłki kwarcowe (grubości do 10 cm), kwarcowo-kruszcowe oraz węglanowe. Złotonośna mineralizacja kruszcowa związana jest z żyłkowo-impregnacyjnymi wystąpieniami pirytu i sfalerytu, którym towarzyszy galena, chalkopiryt oraz podrzędnie arsenopiryt. Złoto i elektrum występująw postaci wrostków w pirycie, żyłek sfalerytowo-galenowych (tnących piryt), jak również w formie drobnoziarnistych wydzieleń (<0,1 mm średnicy) w kwarcu. Elektrum cechuje zmienna zawartość srebra, od 19,7 do 46,9% wag. W profilu otworu wyraźnie zaznacza się pozytywna korelacja ztota z arsenem, ołowiem i miedzią, a także z wysokimi koncentracjami cynku. W strefach złotonośnych oprócz sylifikacji stwierdzono epidotyzację, chlorytyzację oraz kalcytyzację skał klastycznych. Obecność intruzji granodiorytowej w pobliżu otworu oraz licznych górnokarbońsko-dolnopermskich dajek skał magmowych - dacytów, diabazów i andezytów, przecinających strukturalnie zdeformowane metasedymenty ediakaru, wskazuje na związek mineralizacji złotonośnej z rozwojem późnowaryscyjskich pomagmowych procesów hydrotermalnych w strefach oddziaływania intruzji i aktywności tektonicznej.
EN
Recent Polish Geological Institute investigations of the DB-4 drillhole cores from Będkowska Valley (southern part of Małopolska block) documented occurrence of gold in grey-greenish and brown Ediacaran metasedimentary rocks. Elevated concentrations of gold (up to 15 ppm) have been revealed in isolated samples from several intervals, mostly at depths of 253.0 and 584.5 m. Numerous quartz veinlets (up to 10 cm thick), quartz-sulphide and carbonate veinlets occur within those intervals. Gold-bearing mineralization coexists with pyrite and sphalerite veinings and impregnations in association with galena, chalcopyrite and minor arsenopyrite. Gold and electrum occur in a form of inclusions in pyrite, sphalerite-galena veinlets (which crosscut pyrite), and as fine-grained exsolutions(<0.1 mm in size) in quartz. Electrum is characterized by variable contents of silver, in a range from 19.7 to 46.9 wt %. In DB-4 profile, gold shows a positive correlation with arsenic, lead, copper, and zinc. Gold-hosted rocks display silification, epidotization, chloritization and calcitization. Granodiorite intrusion in the vicinity of drillhole and numerous intrusion-related Upper Carboniferous-Lower Permian dacite, diabase and andesite dikes which cut across the Ediacaran structurally-deformed metasediments implies that the formation of gold-bearing mineralization may relate to evolution of late-Variscan postmagmatic hydrothermal processes in zones affected by magmatic and tectonic activity.
EN
In the present contribution we examine possible role of deposits of the Białopole, Lublin, Włodawa and Mazowsze Forma-tions (uppermost Ediacaran to lowermost Cambrian), as well as their presumed lateral equivalents, developed in the Lublin-Podlasie region as a potential source rock for hydrocarbons. The analysed sediments contain marine kerogen of algal and cyanobacterial ori-gin, i.e., predominantly oil prone. In some parts of the analysed area recent TOC could reach 0.65%, however, primary TOC could be significantly higher, as it is indicated by relatively high maturity of the hydrocarbons. Quality of potential source rock increases towards SW. The analysed potential source rock could be, at least partly, responsible for oil and gas shows, commonly observed in the Lower and Middle Cambrian sandstone horizons.
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