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EN
Sedimentary features of the Cambrian-age succession transected in seven borehole cores sited in the Podlasie region document vertical and lateral variations of shallow-marine sedimentary facies, deposited at the rifted western margin of the Baltica Palaeocontinent. The boreholes are distributed along two lines of cross-section (E–W and NE–SW) running roughly perpendicular to the margin of the palaeocontinent. The easternmost borehole represents a proximal setting located on a relatively stable, shallow basement in the east; the remaining boreholes document conditions of deposition in the subsiding shallow-marine basin, extending towards the SW. Fourteen sedimentary facies defined on the basis of their lithological and sedimentary features are interpreted in terms of the sedimentary environments they represent. Strata deposited upon the stable craton in the east document a stratigraphically condensed succession of proximal facies, 240 m thick, whereas a sequence three times thicker is positioned distally, 170 km to the west. Facies associations in the proximal section represent the lower to upper shoreface in the lower part of the section and evolve upwards to the intermediate shoreface. Facies complexes in the remaining, intermediate and distal areas form a symmetrical megasequence, composed of a positive (i.e., fining-upwards – FU) transgressive sequence, overlain by a negative (coarsening-upwards – CU) regressive sequence. The vertical arrangement of the sedimentary subenvironments during the transgression indicates a tidally influenced shoreline followed by oscillations between the swash zone, the upper, intermediate and lower shoreface, and the offshore. The symmetry of the megasequences and the rhythmic pattern of the component facies complexes indicate that the intensity of supply in the terrigenous material and the efficiency of its reworking and redistribution within the basin were similar during the transgression and the regression. The facies types and variations within the basal part of the succession reflect syndepositional movements of tectonic blocks parallel to the rifted basin margin. Differences in total thickness and facies associations between the two lines of cross-section approximately perpendicular to the basin margin indicate that sedimentation was also influenced by a synsedimentary hinge fault, extending in a WSW–ENE direction.
EN
A microfauna of small shelly fossils (SSF) is reported here for the first time from middle Cambrian (Series 3, Stage 5) subsurface strata of the Torgau-Doberlug Syncline (TDS), Central Germany. Considering that this microfauna is strongly limited and poorly preserved the material is quite abundant and diverse. The assemblage consists of molluscs (pelagiellids, bivalves), coeloscleritophorans (chancelloriids, halkieriids), poriferids, protoconodonts, cambroclaves, hyoliths, brachiopods, and disarticulated echinoderm remains. Additionally, a probable pterobranch hemichordate is noted. The assemblage is dominated by epifaunal suspension feeders from mid- to outer shelf depositional settings. Stratigraphically it represents (together with rare trilobites) the oldest middle Cambrian (Series 3, Stage 5) fauna known from Central Germany and the entire Saxothuringian Zone. Regardless the taphonomic problems related to the SSF occurrence, close palaeobiogeographic relations are indicated with the Mediterranean shelf of West Gondwana (especially with the areas of southwestern Europe and Morocco). The reported microfauna coupled with recent trilobite and palynomorph research supports assumptions that the Cambrian succession in the TDS is by far more complete than hitherto suggested, emphasizing its importance as a region yielding Cambrian rocks in Central Europe.
EN
Amongst the materials collected from the Cambrian outcrops in the Holy Cross Mountains by priest professor Włodzimierz Sedlak, there is a holotype and only specimen of Helcionella polonica, as well as a rock fragment with casts of medusoids on its surface. We decided to revise these materials for their importance to discussions on the early molluscs’ size and the medusae fossil record; as well as for the critical nature of previously published revisions of taxa erected by Sedlak.
EN
The southern slope of Łysica Mountain, which is the highest elevation of the Holy Cross Mountains, is comprised of three lithological complexes divided by parallel fault zones. The uppermost part of the succession consists of quartzitic sandstone of the Wiśniówka Formation. The formation is underlain by a complex of sandstone with mudstone interbeds, with black claystone underneath, which is exposed in the upper part of the Glęboczka ravine succession. The strata of the first and the third complexes dip northward, whereas those of the second complex dip southward. In the fault-bound zone between the second and the third complexes, there are concentrations of weathering iron ore. The black claystone, which is lithologically similar to this of the Pepper Mountains Formation, contains a taxonomically rich assemblage of organic-walled microfossils (acritarchs) diagnostic of the Upper Cambrian (Lower Furongian) successions. The new record of microfossils allows determining the age of the succession composing the Łysogóry Mountains for the first time in the history of regional geological investigation.
EN
The Orlica–Śnieżnik Dome in the Sudetes, the NE Bohemian Massif, embraces two formations of felsic gneisses of controversial origin and evolution. Our study shows that despite similar geochemical signatures, they carry systematic minor differences in mineral, isotope, zircon and geothermobarometric characteristics. Four variants of the Gierałtów gneisses include migmatites and have a longer structural history than the Śnieżnik augen orthogneisses. U-Pb SHRIMP analyses yielded U-Pb ages of ~500 Ma for cores and ~498 Ma for wide outer parts of zircon grains in the twice-folded Gierałtów gneisses, and an age of ~500 Ma for a discordant neosome vein. Neoproterozoic metasediments were among precursors of the lithologically diversified Gierałtów Gneiss Formation. First deformation, metamorphism, and migmatisation of these rocks occurred at 515–475 Ma and overlapped with the development and emplacement of a porphyritic S-type granite precursor to the Śnieżnik Gneiss Formation. The metagranite (= Śnieżnik augen orthogneiss) embraced migmatitic xenoliths. Zircon grains from such xenoliths revealed distorted and replaced cores which yielded U-Pb ages that dispersed around 507–487 Ma, whilst wide darker poorly zoned outgrowths yielded ages from ~343 Ma to ~325 Ma (mean ~340 Ma). These outgrowths were interpreted as a record of Carboniferous metamorphism assisted by rich Zr- and U-carrying fluids. The Variscan metamorphic overprint was heterogeneous, and variously affected rocks of the two gneiss formations.
PL
Na podstawie badań przeprowadzonych w obrębie trzech obszarów w Polsce przedstawiono charakterystykę i efekty analiz mikrotermometrycznych inkluzji, występujących w spoiwach i minerałach skał osadowych różnego wieku (od kambru przez perm po paleogen) oraz wypełnionych węglowodorami (HCFI). Inkluzje mają charakter pierwotny i wtórny. Są na ogół jedno- lub dwufazowe. Charakteryzuje je fluorescencja w barwach biało-niebieskich (ropa naftowa) lub niebieskawej (metan), niekiedy żółtej lub czerwonej. Na podstawie barwy świecenia wstępnie oszacowano charakter węglowodorów, które wypełniają te inkluzje i krążą w skałach z tego regionu. Temperatura homogenizacji, która stanowi przybliżenie temperatury zamknięcia fluidu w minerale, wykazuje zmienność związaną z historią geologiczną badanych obszarów. Inkluzje węglowodorów współwystępują w badanych rejonach z inkluzjami solankowymi. Połączenie wyników analiz mikrotermometrycznych inkluzji węglowodorowych z rezultatami badań inkluzji wodnych pozwoliło na szerszą interpretację wyników wszystkich oznaczeń w poszczególnych rejonach. Obecność węglowodorów w inkluzjach świadczy o ich występowaniu i/lub migracji w skałach badanych regionów.
EN
Characteristics and results of microthermometric studies of fluid inclusions which occur in the cements of sedimentary rocks of various ages (from Cambrian through Permian to Paleogene) and filled with hydrocarbons (HCFI) are presented. The inclusions are primary and secondary in origin. They display one or two phases and fluorescence in white-blue (oil) or dull blue (methane) colours, sometimes yellow or red. Based on the fluorescence colour in the ultraviolet light a character of hydrocarbons that fill these inclusions and migrate in the rocks of the region can be estimated. The inclusions are filled with palaeofluids of different compositions. The homogenization temperatures, which correspond to the minimum estimation of the trapping temperatures in minerals, show variability with respect to the geological history of the study area. The hydrocarbon inclusions are often accompanied by brine inclusions. Wider interpretation of all microthermometric analyses was enabled due to the combination of studies on hydrocarbon and aqueous inclusions. The presence of hydrocarbons in inclusions is a proof of their occurrence and/or migration in the rocks of the regions studied.
PL
W pracy przedstawiono wybrane obiekty z południowo-wschodniej części Gór Świętokrzyskich, z rejonu pomiędzy Opatowem a Staszowem, które mogą stać się atrakcyjnymi obiektami geoturystycznymi. Są to złoża środkowodewońskich wapieni i dolomitów oraz dolnokambryjskiego piaskowca kwarcytowego, osady mioceńskich wapieni detrycznych z okolic Smerdyny oraz zamek Krzyżtopór w Ujeździe. W pracy wskazano zjawiska geologiczne, których różnorodność i bogactwo świadczy o bardzo dużym potencjale geoturystycznym omawianego obszaru.
EN
The paper presents selected targets from the south-eastern part of the Holy Cross Mountains, in the Opatów and Staszów area, which could be geotourist attractions. These are the deposits of Middle Devonian limestones and dolomites, Lower Cambrian quartz sandstones, Miocene detrital limestones from the Smerdyna area, as well as the Krzyżtopór Castle in Ujazd. The paper shows the geological diversity and a high geotourist potential of the discussed area.
EN
Quartz arenites and wackes with intercalations of silty shales of the Ociesęki Formation were analysed in small outcrops and one core. The succession contains about forty-three ichnogenera and seventy-four ichnospe- cies, among which thirty-three ichnogenera and fifty-three ichnospecies are described by present author. The formation belongs to the Schmidtiellus-Holmia Superzone and to the Protolenus-Issafeniella Zone. Most strata are totally bioturbated. The diverse and numerous trace fossils represent the Cruziana ichnofacies in the lower part of the formation and the Skolithos ichnofacies in the upper part. A few possibly new ichnospecies of different ichnogenera have been described in open nomenclature. Sedimentary structures and trace fossil assemblages indicate that the older part of this formation was deposited on the upper offshore to lower shoreface, while its younger part was deposited on the lower to middle shoreface, where storm episodes were the main factor controlling sedimentation and the activity of benthos. The trace fossil associations studied are similar to those from the lower Cambrian in many places around the world. The ichnoassociations from the Polish part of the East European Platform and from Sweden, which represent the Baltica palaeocontinent, display the closest similarity.
EN
Three lower Cambrian acritarch assemblages recognized in four outcrops in the vicinity of Kotuszów in the southernmost part of the Palaeozoic inlier of the Holy Cross Mountains span a stratigraphic interval from the uppermost part of the Asteridium tornatum–Comasphaeridium velvetum Assemblage Zone to the Skiagia ornata–Fimbriaglomerella membranacea Assemblage Zone (most probably its lower part). According to current views (Moczydłowska and Yin 2012), this interval corresponds to the upper part of the Fortunian and to Stage 2 of the Terreneuvian Series. The strata yielding the oldest assemblage are thus the oldest precisely documented rocks in the Palaeozoic succession of the Holy Cross Mountains, and the oldest Cambrian rocks exposed on the surface in Poland. The current biostratigraphic scheme for the pre-trilobitic part of the Cambrian System in the Holy Cross Mountains should be modified so that it is based on local acritarch interval subzones.
PL
Przedstawiono charakterystykę i wyniki mikrotermometrycznych badań inkluzji fluidalnych występujących w spoiwie skał osadowych wieku od kambru po perm oraz od jury po paleogen i miocen. Inkluzje mają charakter pierwotny i wtórny; na ogół są jedno- lub dwu-, rzadziej trójfazowe. Wypełniają je paleofluidy o zróżnicowanym składzie i różnej gęstości. Temperatura homogenizacji, która stanowi przybliżenie temperatury zamknięcia fluidu w minerale, wykazuje zmienność związaną z rodzajem spoiwa i z historią geologiczną badanego obszaru. Zasolenie fluidów również jest zmienne i zależy od rodzaju spoiwa i od lokalizacji. Połączenie analiz inkluzji np. z badaniami izotopowymi pozwala na szerszą interpretację wyników oznaczeń mikrotermometrycznych.
EN
Characteristics and results of microthermometric studies of fluid inclusions which occur in the cements of sedimentary rocks of the age oscillating form Cambrian to Permian and from Jurassic to Paleogene and Miocene are presented. The inclusions studied are primary and secondary in origin. They display one, two or, less frequently, three phases. The inclusions are filled by the paleofluids of variable compositions and densities. The homogenization temperature, which corresponds to the minimum estimation of the trapping temperature, shows variability in respect to the cement type and geological history of the study area. Salinities of fluids are also variable in respect to the cement type and locality. Wider interpretation of the microthermometric analyses is enabled when they are combined, e.g., with the isotopic studies.
11
Content available remote AMS of Cambrian volcanic rocks in Barrandian
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.
EN
A new trace fossil Rusophycus inexpectus isp. nov. is described from the Furongian (Upper Cambrian) strata of the Holy Cross Mountains. This ichnospecies is probably non-trilobite in origin and is commonly preserved as an undertrace. This preservation style resembles that of Rusophycus ramellensis Legg, an index fossil of the Cambrian Series 3. Therefore, previous workers misinterpreted material from the Wiśniówka Sandstone Formation as Rusophycus ramellensis Legg (recorded by them as Cruziana barbata) and put the Cambrian Series 3 and Furongian boundary within this unit. Rusophycus inexpectus isp. nov differs from Rusophycus ramellensis Legg: 1) in having a smooth trapezoidal area behind the lobes; 2) in the presence of a direct contact between the endopodal lobes and cephalic margin imprints and 3) in the restriction of the occurrence of the endopodal lobes and scratches to the cephalic region of the trace fossil. Care must be taken, when dealing with the undertrace preservation style of Rusophycus ramellensis Legg in other assemblages, as it may represent Rusophycus inexpectus isp. nov.
EN
The paper presents results of valorization of geosites in the Łysogóry Region of the Holy Cross Mountains, which warrant creation of the Łysogóry Geopark. Numerous geosites of different Paleozoic rocks offer a great educational potential, combining many fields of knowledge, such as geology, geomorphology, paleontology, paleoecology, ancient metallurgy industry and historical monuments. Geodiveristy makes this area very attractive for geotourism.
EN
The Burgess Shale of the Canadian Rocky Mts is one of the most well-known occurrences of Cambrian strata exhibiting exceptional preservation of a soft-bodied fauna. While Lagerstätten of the Burgess Shale-type fauna have been recognized in almost all parts of the world and in all Cambrian series, the circumstances and mechanisms allowing for such a unique mode of preservation have remained enigmatic. Of particular debate has been the reconstruction of prevailing redox conditions. This brief contribution overviews the fauna and recent advances towards understanding the sedimentary and taphonomic conditions prevailing during deposition.
16
Content available remote Cambrian phytoplankton of the Brunovistulicum : taxonomy and biostratigraphy
EN
The paper presents the results of detailed palynological studies carried out on the Cambrian deposits of the Brunovistulicum, a characteristic regional unit distinguished in sub-Devonian geology in southern Poland and NE Czech Republic. The material studied consists of drillcore samples collected from 22 boreholes that have penetrated Cambrian in southern and north-eastern parts of the Upper Silesian Block (USB) and 3 boreholes located in the Moravia region (Czech Republic). Within those boreholes, complexes of lithologically differentiated clastic rocks have been encountered below Jurassic, and Lower or Middle Devonian deposits. The age of these sediments, apart from the Goczałkowice IG 1 profile, was determined only on the basis of palynological studies. Majority of the investigated rock samples yielded very rich usually well preserved microfloristic material that allowed to make taxonomic revisions of analysed acritarch associations. Five new genera, nineteen new species and eleven species new combinations are proposed. The new and revised taxa include mainly those that appear in the Cambrian Series 2 and forms characteristic for the Cambrian Series 3. These are the following important new genera as: Ichnosphaera, Lechistania, Eklundia, Parmasphaeridium and Turrisphaeridium. The taxonomic revision and systematic analysis of acritarch associations described from the Cambrian of Brunovistulicum allowed to establish the succession of microfloral assemblages. As a result of the present studies nine distinct regional assemblage acritarch zones have been recognised – BAMA I to BAMA IX, correlated with the Cambrian series: Terreneuvian, Series 2, and Series 3. The BAMA I – Pulvinosphaeridium antiquum–Pseudotasmanites and the BAMA II Asteridium tornatum–Comasphaeridium velvetum zones are distinguished in the oldest Cambrian deposits of the Brunovistulicum and are correlated with the Platysolenites Zone. Acritarch assemblages characteristic for the older one were documented in the Borzeta Formation in the eastern margin of the Upper Silesian Block. The acritarch association of the BAMA II constrains the biostratigraphic position of the Mogilany Member of Goczałkowice Formation in the USB area. The BAMA III–VI acritarch assemblage zones: Ichnosphaera flexuosa–Comasphaeridium molliculum, Skiagia–Eklundia campanula, Skiagia–Eklundia varia and Volkovia dentifera–Liepaina plana are recognised in the Goczałkowice Formation of both the Upper Silesian and Brno blocks and comprise deposits of Schmidtiellus, Holmia and Protolenus trilobite zones in the studied area. The BAMA VII to BAMA IX zones are correlated with Series 3 of the Cambrian System and were established in the Sosnowiec Formation known only from the Sosnowiec IG 1 borehole in the Upper Silesian Block area. The BAMA VII Ammonidium bellulum–Ammonidium notatum Zone is here correlated with trilobite Acadoparadoxides oelandicus Zone, while BAMA VIII Turrisphaeridium semireticulatum and BAMA IX Adara alea–Multiplicisphaeridium llynense zones are regarded as equivalents of the Paradoxides paradoxissimus Zone. The present study indicates that the oldest Cambrian (Terreneuvian) sediments containing BAMAI Zone assemblages were deposited only in the eastern part of the Upper Silesian Block. Younger sediments, from the Terreneuvian and Series 2 with BAMA II–VI Zones assemblages were developing over much larger areas of the Upper Silesian and Brno blocks. Sediments of the Series 3 with BAMA VII–IX assemblages are known only from the northern part of the USB. The Furongian sediments, not yet found in the study area, potentially may occur in the northern part of the Block, where the Ordovician strata were found. Nevertheless, a reliable reconstruction of the Early Palaeozoic deposition within the Brunovistulicum still remains an open question, which can be solved only by new borehole data.
PL
W pracy przedstawiono wyniki szczegółowych badań palinologicznych wykonanych dla utworów kambryjskich rozpoznanych na obszarze Brunovistulicum, regionalnej jednostki tektonicznej położonej na południu Polski i w północno-wschodnich Czechach. Materiał do badań stanowiły próbki skał z 22 otworów wiertniczych zlokalizowanych w obszarze bloku górnośląskiego oraz z 3 wierceń wykonanych na Morawach (blok Brna). W wierceniach tych pod utworami jury, dewonu dolnego lub środkowego nawiercono zróżnicowane litologicznie kompleksy skał klastycznych, które poza jednym profilem - Goczałkowce IG 1 - pozbawione są przewodnich mikroskamieniałości, a ich kambryjski wiek został ustalony na podstawie badań palinologicznych. Uzyskany w trakcie badań bogaty i w większości dobrze zachowany materiał mikroflorystyczny umożliwił przeprowadzenie rewizji wielu taksonów akritarch, w tym wykreowania 5 nowych rodzajów oraz wyróżnienia 19 nowych gatunków i 11 nowych kombinacji gatunkowych. Nowe i rewidowane taksony to głównie gatunki występujące w utworach oddziału 2 i formy charakterystyczne dla oddziału 3 systemu kambryjskiego. Do najważniejszych należą następujące nowe przewodnie rodzaje: Ichnosphaera, Lechistania, Eklundia, Parmasphaeridium i Turrisphaeridium. Przeprowadzone analizy taksonomiczne zespołów akritarch udokumentowanych w utworach kambru Brunovistulicum pozwoliły na wyznaczenie w tym obszarze 9 regionalnych poziomów mikroflorystycznych - BAMA I do BAMA IX, które datują trzy kolejne oddziały kambru: terenew, oddział 2i3. Poziomy BAMA I Pulvinosphaeridium antiquum-Pseudotasmanites i BAMA II Asteridium tornatum-Comasphaeridium velvetum rozpoznano w najstarszych utworach kambru Brunovistulicum, gdzie zostały skorelowane z poziomem Platysolenites. Zespoły akritarch charakterystyczne dla poziomu BAMA I stwierdzono w utworach formacji z Borzęty udokumentowanych we wschodniej brzeżnej części bloku górnośląskiego. Kolejna asocjacja BAMA II datuje wiek kompleksu skalnego wyróżnionego w obszarze bloku górnośląskiego jako ogniwo piaskowców skolitusowych z Mogilan formacji z Goczałkowic. Zespoły akritarch charakterystyczne dla poziomów BAMA III-VI: Ichnosphaeraflexuosa-Comasphaeridium molliculum, Skiagia-Eklundia campanula, Skiagia-Eklundia varia i Volkovia dentifera-Liepaina plana, które korelowane są z poziomami Schmidtiellus, Holmia i Protolenus udokumentowano w osadach formacji z Goczałkowic, rozpoznanych w obszarach bloku górnośląskiego i bloku Brna. Utwory odddziału 3 kambru w analizowanym obszarze dokumentują trzy poziomy akritarchowe BAMA VII-IX, stwierdzone w osadach formacji z Sosnowca, udostępnionych otworem wiertniczym Sosnowiec IG 1 na bloku górnośląskim. Poziom BAMA VII Ammonidium bellulum-Ammonidium notatum należy wiązać z poziomem Acadoparadoxides oelandicus, natomiast dwa pozostałe poziomy BAMA VIII Turrisphaeridium semireticulatum i BAMA IX Adara alea-Multiplicisphaeridium llynense z poziomem Paradoxidesparadoxissimus. Z przeprowadzonych badań wynika, że najstarsze osady kambryjskie - terenewu - zawierające zespoły BAMA I tworzyły się tylko w części wschodniej bloku górnośląskiego. Osady młodsze, terenewu i oddziału 2 z zespołami BAMA II-VI rozwijały się na znacznie większym obszarze bloku górnośląskiego i bloku Brna. Osady oddziału 3 z zespołami BAMA VII-IX tworzyły się w północnej części bloku górnośląskiego. Obecność osadów furongu w analizowanym obszarze jest wielce prawdopodobna, mogą one występować w północnej części bloku, tym bardziej, że zostały tam już udokumentowane utwory ordowiku. Wiarygodne i prawidłowe odtworzenie rozwoju sedymentacji osadów dolnopaleozoicznych na obszarze Brunovistulicum pozostaje zagadnieniem otwartym, które można rozwiązać jedynie za pomocą nowych otworów wiertniczych pozwalających na poznanie pełniejszych profili tych utworów.
EN
In general, the trace fossil Rusophycus, preserved as a concave-upward structure on the top of a bed, is considered to be a fossilized marking, made by a trace maker. The structures described from the Cambrian (Furongian) of central Poland are genetically related to Rusophycus. However, despite their occurrence on the tops of beds, they are not fossilized traces, but compaction-related features, resulting from differential sandstone and mudstone compaction with possible mediation by organic-rich, heterolithic sediments. The preservation of these structures probably was influenced by biofilms or biomats.
EN
Marine carbonates and siliciclastic rocks of the Burj Formation in Jordan include paucispecific trilobite associations of the (traditional) Lower. Middle Cambrian boundary interval. Comprehensive new material of these trilobites allows a review of their taxonomy and systematic positions as well as a refined morphological description and a reconsideration of previous interpretations of their stratigraphic position and thus the correlation of the fossiliferous beds. In addition to the classic species Kingaspis campbelli (King, 1923) and Redlichops blanckenhorni Richter and Richter, 1941, Timnaella? orientalis (Picard, 1942) and Hesa problematica Richter and Richter, 1941, the discussed trilobites include Issalia gen. nov. with Issalia scutalis gen. nov., sp. nov., Tayanaspis gen. nov. with Tayanaspis bulbosus gen. nov., sp. nov., Uhaymiria gen. nov. with Uhaymiria glabra gen. nov., sp. nov., Cambrunicornia? jafnaensis sp. nov., Myopsolenites palmeri (Parnes, 1971), M. hyperion sp. nov., and Enixus cf. antiquus (Chernysheva, 1956). Myopsolenites boutiouiti Geyer and Landing, 2004 is now regarded as a junior synonym of Myopsolenites altus (Lian and Gozalo, 1986). A detailed discussion of the correlation with a focus on global aspects provides clues for the utility of potential index fossils for the global Cambrian Series 3 and Stage 5.
EN
Ten ichnogenera and seven ichnospecies are described from the Czarna Shale Formation, possibly representing the Terreneuvian and Cambrian Series 2 of the Holy Cross Mountains. Moreover, five other ichnotaxa are described in open nomenclature. Phycodes circinatus,Taenidium isp., Trichichnus linearis and ?Dictyodora isp. are described from the Cambrian of the Holy Cross Mountains for the first time. The stratigraphic ranges of Trichichnus linearis and Phycodes circinatus are extended. The trace fossil assemblage and associated, sedimentological features point to deposition in the upper and lower offshore. Periodic, anoxic events may have occurred on the sea bed.
EN
Quantity, genetic type and maturity of organic matter dispersed in the Lower Palaeozoic sequence from the Lower Cambrian to Silurian strata of the Polish and Ukrainian parts of the Carpathian Foredeep basement in the Tarnogród–Stryi area were evaluated based on the results of geochemical analyses of 475 rock samples collected from 45 wells. The best source rocks were found in the Silurian strata where the present total organic carbon (TOC) content is up to 2.6 wt%. They occur in the vicinity of Wola Obszańska, where the median of the present and the initial total organic carbon (TOC) contents in the individual wells amount to 0.98 and 1.6 wt%, respectively. The Cambrian and Ordovician strata have a poorer hydrocarbon potential and their present TOC content never exceeds 1 wt%. In all of the investigated Lower Palaeozoic strata, organic matter is represented by the oil-prone Type-II kerogen deposited in anoxic or sub-oxic conditions. The maturity of source rocks ranges from early mature (the initial phase of the low-temperature thermogenic processes) in selected zones of the Silurian strata in the vicinity of Wola Obszańska, through the middle and the final phase of “oil window” in the Ordovician and Cambrian strata in the Polish part of the study area, to the overmature stage in the Ordovician strata in the south-eastern part of the study area (Ukraine).
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