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EN
This paper reviews all available geological data on the Tajno Massif that intruded the Paleoproterozoic crystalline basement of NE Poland (Mazowsze Domain) north of the Teisseyre-Tornquist Zone, on the East European Craton. This massif (and the nearby Ełk and Pisz intrusions) occurs beneath a thick Mesozoic-Cenozoic sedimentary cover. It has first been recognized by geophysical (magnetic and gravity) investigations, then by drilling (12 boreholes down to 1800 m). The main rock types identified (clinopyroxenites, syenites, carbonatites cut by later multiphase volcanic/subvolcanic dykes) allow characterizing this massif as a differentiated ultramafic, alkaline and carbonatite complex, quite comparable to the numerous massifs of the Late Devonian Kola Province of NW Russia. Recent geochronological data (U-Pb on zircon from an albitite and Re-Os on pyrrhotite from a carbonatite) indicate that the massif was emplaced at ~348 Ma (Early Carboniferous). All the rocks, but more specifically the carbonatites, are enriched in Sr, Ba and LREE, like many carbonatites worldwide, but depleted in high field strength elements (Ti, Nb, Ta, Zr). The initial87Sr/86Sr (0.70370 to 0.70380) and ɛNd(t) (+3.3 to +0.7) isotopic compositions of carbonatites plot in the depleted quadrant of the Nd-Sr diagram, close to the “FOcal ZOne” deep mantle domain. The Pb isotopic data (206Pb/204Pb <18.50) do not point to an HIMU (high U/Pb) source. The ranges of C and O stable isotopic compositions of the carbonatites are quite large; some data plot in (orclose to) the “Primary Igneous Carbonatite” box, while others extend to much higher, typ i cally crustal ẟ18O and ẟ13C values.
EN
This study estimates the reservoir properties of the Carboniferous deposits in the southeastern part of the Lublin Basin based on diagenetic and sequence stratigraphic patterns. Depositional sequences distinguished represent the following environments/processes: shallow clay and carbonate shelves, deltaic, fluvial, and hyperconcentrated flow while para- sequences (cyclothems), maximum regression-initial transgression surfaces (T), maximum flooding surfaces (MFS) and also lowstand (LST), transgressive (TST) and highstand (HST) systems tracts have been recognised. Sequences recognized may be linked to the global stratigraphic division of the Carboniferous, thus providing a time framework and environ¬mental context for petrographic and petrophysical examinations. The reservoir properties were found to be clearly controlled by depositional environment, diagenetic history and burial. The best properties were recognized in sandstone lithosomes formed in braided, meandering and anastomosed fluvial channels and hyperconcentrated flows which fill the incised valleys and belong to the LST. They are characterized by good porosity reaching up to 15.1%. The TST and HST deposits are represented chiefly by claystones, mudstones and limestones that formed in a shallow shelf and deltaic environment, being sealing intervals. The diagenetic history of sandstones comprises eo-, meso- and telodiagenetic phases. The major processes acting during the first of these were mechanical compaction, dissolution of mineral grains, formation of predominantly quartz overgrowths around the quartz grains, and crysialiizaton of kaolinite. During mesodiagenesis, cementation with quartz, kaolinite and carbonates continued along with the formation of dickite and fibrous illite; moreover, mineral grains were dissolved and chemical compaction set in. The effects of telodiagenetic processes were feldspar dissolution and precipitation of kaolinite. During diagenesis the maximum temperature affecting the Carboniferous deposits was ~120°C. Compaction and cementation were the main factors responsible for the reduction of porosity by approximately 55 and 38%, respectively. One of the major diagenetic processes was dissolution resulting in the formation of secondary porosity. The Serpukhovian and Bashkirian sandstones from sequence 11 show good reservoir potential, while those from sequences 6, 9, 10, 12-14 only fair potential.
EN
The Family Kumpanophyllidae Fomichev, 1953, synonymised by Hill (1981) with the Family Aulophyllidae Dybowski, 1873, is emended and accepted as valid. The new concept of this family, based on both new collections and discussion on literature data, confirms the solitary growth form of its type genus Kumpanophyllum Fomichev, 1953. However, several fasciculate colonial taxa, so far assigned to various families, may belong to this family as well. The emended genus Kumpanophyllum forms a widely distributed taxon, present in Eastern and Western Europe and in Asia. Its Serpukhovian and Bashkirian occurrences in China vs Bashkirian occurrences in the Donets Basin and in Spain, may suggest its far-Asiatic origin, but none of the existing taxa can be suggested as ancestral for that genus. Thus, the suborder position of the Kumpanophyllidae remains unknown. Four new species: K. columellatum, K. decessum, K. levis, and K. praecox, three Kumpanophyllum species left in open nomenclature and one offsetting specimen, questionably assigned to the genus, are described.
EN
The paper provides new results of palynological studies of rocks from the Świebodzice Unit. An abundant Carboniferous miospores were found in rocks of the Pogorzała Formation from the southern part of this unit. These miospores occur in rocks containing also macrofloral and marine macrofaunal fossils, partly reworked, which were usually considered Upper Devonian. Two miospore sub-assemblages of different ages and colours have been distinguished. One of them consists of poorly preserved miospores, dark in colour, which indicate the Late Visean–Serpukhovian age of the rocks. The other sub-assemblage, found only in a few samples, consists of much lighter and well-preserved miospores of the Asturian age. Their presence is considered as a result of stratigraphical leakage. Observation of the miospore colour indicates that the thermal event occurred after the Late Devonian and before the Asturian and the palaeotemperature exceeded ~180°C. These new data indicate that the geological history of the Świebodzice Unit lasted longer and was much complex than it was previously considered.
EN
Early Carboniferous (late Tournaisian) conodonts, recovered from siliceous shales and silicites of the Nyan-Vorga Formation within the Lemva tectonic belt of the Polar Urals (Russia), include the biostratigraphically important taxa Siphonodella lanei, Gnathodus typicus, Dollymae hassi, and Scaliognathus anchoralis, marking the following conodont zones of the upper Tournaisian: crenulata, typicus, and anchoralis. Associated species include representatives of genera Siphonodella, Polygnathus, Pseudopolygnathus, Dollymae, Gnathodus, Kladognathus, and Idioprioniodus. These conodont faunas provide the first biostratigraphically constrained correlations between bathyal deposits of the Lemva Allochthone in the Polar Urals and the “standard” conodont zonation. Ostracodes found in the silicite of the typicus Zone are represented by Sagittibythere ? sp. and Tricornina (Bohemia) sp. The ostracodes are reported from the bathyal deposits of Urals for a first time. The traces of the global Mid-Aikuanian Event are recognized in the upper part of the Tournaisian bathyal succession. This event led to turnover in conodont associations and is followed by increasing in conodont diversity.
PL
W artykule przedstawiono ocenę zawartości jonu barowego dopływającego z utworów karbonu do kopalń w solankach, a następnie zmian ilości tego szkodliwego dla środowiska wodnego składnika, wynikających z procesów zachodzących w węglonośnych utworach oraz w wyrobiskach górniczych w czasie przepływu wód kopalnianych na powierzchnię, do środowiska naturalnego wód powierzchniowych.
EN
The article presents an assessment of barium ion content inflowing from the Carboniferous measures to the mines in the brine, followed by changes in the amount of this component harmful for the water environment resulting from the processes taking place in the coal-bearing formations and in mine workings during the flow of mine waters to the surface, to the natural environment of surface waters.
PL
W trakcie wieloletnich badań geologicznych karbonu lubelskiego udowodniono występowanie kilku ważnych poziomów litologicznych, które są przydatne do przeprowadzania korelacji profilu karbonu z różnych rejonów Lubelskiego Zagłębia Węglowego. Jednym z nich jest poziom iłowców z Dunbarella usytuowany w dolnej części formacji z Lublina w bezpośrednim stropie pokładu węgla 395(305). Jest to poziom jednorodny litologicznie, ale zmienny pod względem zawartości skamieniałości fauny. Część dolna, o grubości do 0,6 m, zawiera skorupy małżów słodkowodnych z rodzaju Carbonicola i Naiadites. Wyższa część, o grubości około 15 m, oddzielona cienką, 0,35 m warstwą węglanową, zawiera skamieniałości fauny morskiej reprezentowanej przez małże w tym Dunbarella, ramienionogi, głowonogi i ślimaki, a w części stropowej o grubości do około 5,0 m, oprócz fauny Lingula charakterystycznej dla środowisk przejściowych, pojawiają się skamieniałości małżów słodkowodnych Naiadites i Anthracosia. Poziom ten definiuje spąg serii węglonośnej z ekonomicznymi pokładami węgla, a ponadto granicę między westfalem A i B.
EN
Several lithological horizons of correlative importance have been distinguished in the Carboniferous section of the Lublin Coal Basin (Poland). One of them is the marine horizon with Dunbarella, that occurs as a claystone horizon in the lower part of the Lublin Formation, close to the coal seam no. 395 (305). Marine horizon with Dunbarella is lithologicaly unified but unique as it refers to the presence of fauna fossils. In the lower part of this horizon of 0,6m in thickness, shells of freshwater molluscs of Anthracosia and Naiadites occur. In the upper part of 15m in thickness, fossils of marine fauna occur, which are represented by: molluscs (including Dunbarella), brachiopods, cephalopods and gastropods. At the top part of the horizon of 5m in thickness, fossils of Lingula characteristic for brackish water environments occur. The presence of freshwater molluscs of Naiadites and Anthracosia is also indicative of the top part of the horizon. The boundary of marine horizon with Dunbarella between Westphalian A and Westphalian B is acknowledged as the indicative horizon of the bottom part of economic coal-bearing formation of the Carboniferous in the Lublin Coal Basin.
EN
The paper presents the characteristics of prospective zones identified for the first time within the lower Palaeozoic shale formations occurring in the Baltic-Podlasie-Lublin Basin and within the Carboniferous shale, sandstone, and mixed shale-sandstone complexes (the so-called hybrid complexes) in the basin of south-western Poland. The lateral and vertical ranges of these zones are determined based on specific criteria using the results of various research methods and analyses, i.e.: stratigraphic, sedimentological, mineralogical, petrological and geochemical of organic matter, petrographic and petrophysical, including interpretation of well logs. Archived geological materials and those coming from the boreholes drilled recently in the concession areas were also used. Four prospective zones have been distinguished in the lower Palaeozoic of the so-called shale belt: SP1, SP2, SP3 and SP4. The most prospective area for the occurrence of unconventional hydrocarbon deposits in shale formations is the Baltic region – the Łeba Elevation, where there are all four perspective zones, only partially covering the range of potentially prospective formations. In each of these zones, both liquid and gas hydrocarbons can be expected in this area. Due to the low percentage of organic matter, the lowest hydrocarbon generation potential is attributed to the Lublin region. However, the low values of this parameter are compensated by other parameters, i.e. the considerable thickness and lateral extent of zone SP4 corresponding partly to the Pelplin Formation. In the Carboniferous rocks of south-western Poland, seven prospective zones have been distinguished in four borehole sections. Four of them are “tight” zones in compact sandstones, while the other three zones represent a hybrid type in complexes with mixed lithology. No prospective zones have been defined in complexes with homogeneous shale lithologies. Determination of lateral extents of the identified zones has not been possible due to the scarcity of data on the geological structure and stratigraphy of the Carboniferous succession in the study area
EN
Studies that have recently been carried out by the Polish Geological Survey aim at, among others, deepening and supplementing the knowledge of unconventional hydrocarbon systems in Poland, including petroleum systems of the lower Palaeozoic in the Polish part of the East European Craton and of the Carboniferous in the South-Western Poland. The article presents the main principles and objectives of the research and the results of the project titled “Identification of prospective zones for unconventional hydrocarbon accumulations in Poland, stageI”,which is the only project that uses a wide range of recently conducted regional geology research and laboratory analyses, integrated with geological information derived from newly drilled boreholes. Geological constraints for the occurrence of unconventional hydrocarbon deposits in the Cambrian, Ordovician Silurian and Carboniferous rocks are presented. What is emphasized is the need to continue the work and to extend it to new research directions aimed at petroleum system modelling (e.g.burial history and analysis of hydrocarbon generation), and the need to refine and clarify some of the results obtained, supplementing them with an analysis of the latest data from newly drilled boreholes.
EN
The study deals with clay-silt shales occurring in the lower Palaeozoic basin at the western slope of the East European Craton, and sandstones known from the Carboniferous Basin of SW Poland (basement of theFore-SudeticHomocline).The clay groundmass of the shales consistslargely of illite, and the silt fraction is made up of quartz with a variable admixture of feldspars. Quartz and carbonate cements are common, while pyrite, kaolinite and phosphate cements are rare. The clay groundmass reveals microporosity in the form of microchannels paralleling illite plates, and visible with in mica packets. Carboniferous sandstones are represented mostly by sublithic or subarkosic wackes and rarely by lithic, sublithic or subarkosic arenites. The pore space between sand grains is completely filled by clayey matrix. Both porosity and permeability are very low in the sandstones.
EN
The aim of the study was to present the use of archival welllogs for quantitative determination of organic matter (TOC wt.% ). The study was conducted in the lower Palaeozoic rocks of the Baltic Basin and Podlasie-Lublin Basin as well as in the Carboniferous rocks of the Fore-Sudetic Homocline basement. In many wells, sonic logging has not been run at all or run to a limited extent. In such cases, a neural network method was used to estimate the interval time. Then, continuous analysis was carried out for quantitative determination of organic matter content (TOC) using the CARBOLOG method. Finally, well log interpretation was performed for six wells in the Podlasie-Lublin Basin, five wells in the Baltic Basin, and five wells in the Fore-Sudetic Homocline basement. This article presents examples of results obtained for two wells.
EN
The Petřkovice Member is the basal unit of the paralic succession of the Ostrava Formation of the Upper Silesian Basin. This member is a valuable source of information about the transition from a marine basin filled with siliciclastic sediments into a paralic basin with the beginning of coal-bearing sedimentation. Models of: (1) the number of coal seams, (2) their total thickness, and (3) the coal content with respect to the total thickness of the succession were created to describe and assess the coal-bearing capacity of the Petřkovice Member. The authors present models for coal seam thicknesses exceeding either 10 or 40 cm. The coal-bearing capacity of the Petřkovice Member is very low. The average share of coal seams thicker than 0.1 m is 3%. The share of coal seams with a thickness that exceeds 0.4 m is only 1.66%. Moreover, in large areas of the basin, in the N and NE parts, the coal-bearing capacity is close to zero, because coal seams of greater thickness were detected only locally there. Based on these models and on other geological data, it is obvious that the onset of coal sedimentation was gradual and limited to particular sites showing the greatest subsidence of the basin floor. In places where minor subsidence took place, there were likely unfavorable conditions for accumulation of organic matter.
EN
Among the rich material of chondrichthyan microremains from the Indian Cave Sandstone (Upper Pennsylvanian, Gzhelian) near Peru, Nebraska, USA, housed at the Carnegie Museum of Natural History, there occur almost sixty teeth representing Euselachii. They belong to at least seven species, presenting various types of heterodonty. Two new species are described, viz. Ossianodus nebraskensis gen. et sp. nov., whose dentition is similar to that of certain Mesozoic hybodonts, and Sphenacanthus tenuis sp. nov. with minute teeth of protacrodont design. Most of the euselachian teeth served to crush or grind prey, and some had the potential to clutch, but cutting teeth are absent from the fauna.
PL
W strefie przejściowej pomiędzy siodłem głównym a niecką główną występują osady warstw orzeskich, które ostatnio poznano jednym otworem z powierzchni. Rozpoznano część profilu, który uległ znacznym, daleko zaawansowanym procesom wietrzeniowym, o czym świadczy występowanie skał słabo zdiagenezowanych i luźnych o nietypowych dla karbonu brązowo-żółtych barwach. Pobrane z analizowanego profilu próbki skał okruchowych zostały poddane badaniom petrograficzno-mineralogicznym. Na ich podstawie stwierdzono, że reprezentują one piaskowce, mułowce oraz iłowce, których jednym z głównych składników jest kwarc. Badany fragment profilu pod względem litostratygraficznym należy do warstw orzeskich reprezentujących górną część serii mułowcowej (moskow).
EN
Orzesze Beds, which recently have been known by one bore hole from the surface, occur in the transition zone between the main saddle and the main basin sediments. The part of profile under the advanced weathering processes has been recognized, as evidenced by the occurrence of poorly diagenetically formed rocks and loose rocks characterized by unusual for Carboniferous brown-yellow colors. Petrographical and mineralogical tests were carried out for the samples from the analyzed profile. On this basis, it was found that they represent sandstones, mudstones and claystones, which mainly contain quartz. The tested fragment of lithostratigraphic profile belongs to Orzesze Beds representing the upper part of mudstone series (Moscovian).
EN
The main aim of this study is to define precisely the age of the alkaline basalts occurring within the lowermost part of Carboniferous succession in the northeastern part of LublinBasin(drill core Parczew IG-7 and IG-9; SE Poland). The new, whole-rocks 40Ar/39Ar data constrain the age of volcanic activity and emplacement of alkaline basalts to the Late Tournaisian (348 ± 0.8 Ma) with possible prolongation to the Middle Visean (338.5 ± 0.7 Ma). The younger age is however of evidently poorer quality than the older one. The new data caused to correlate the volcanic processes occurring within the Lublin Basin with alkaline intrusions drilled inNE Poland inside the Paleozoic cover of the East European Platform. They also correspond to the volcanoclastic levels defined in different parts of the Trans European Suture Zone in Poland.
PL
Na obszarze środkowej części masywu małopolskiego, w ośmiu profilach wiertniczych wykonano badania paleotermiczne utworów węglanowych dewonu, karbonu i triasu na podstawie przeobrażenia termicznego substancji organicznej zawartej w konodontach. Na podstawie stopnia przeobrażenia barw konodontów pod wpływem temperatury (wskaźnik CAI – Colour Alteration Index) określono zakresy paleotemperatur jakim zostały poddane skały zawierające te organizmy. W otworze wiertniczym Węgrzynów IG 1 utwory żywetu górnego, franu, famenu i karbonu dolnego (turnej, wizen) mają wskaźnik CAI od 3 (dla żywetu) do 2 (dla karbonu dolnego). Wskazuje on na podgrzanie w zakresie 60‒110°C, na obszarze frontu waryscydów o wysokiej wartości paleogradientu termicznego. Dla profilu dewonu górnego w otworze Pągów IG 1 wartość CAI 4,5 dokumentuje stopień podgrzania skał do temperatury powyżej 230°C, w wyniku udziału podwyższonego strumienia cieplnego w rejonie strefy tektonicznej. W utworach triasu wskaźnik CAI 1‒1,5 świadczy o podgrzaniu skał w granicach 50‒90°C. Stosunkowo niska paleotemperatura materii organicznej w utworach triasu wskazuje, że utwory dewonu i karbonu osiągnęły dojrzałość termiczną w późnym karbonie, przed orogenezą waryscyjską. Objawy ropy naftowej i gazu ziemnego w utworach dewonu i karbonu centralnej części masywu małopolskiego mogą świadczyć o ich perspektywiczności w aspekcie poszukiwań bituminów.
EN
A paleothermal study of Devonian, Carboniferous and Triassic carbonate rocks was carried out in eight boreholes from the central part of the Małopolska Massif by using data on thermal alteration of organic matter contained in conodonts. The maturity of organic matter expressed as the CAI (Colour Alteration Index) values was used to calculate palaeotemperatures that affected the conodont-bearing rocks. In the Węgrzynów IG 1 borehole, the CAI values for the Upper Givetian, Frasnian, Famennian and Lower Carboniferous rocks range from 3 (Givetian) to 2 (Lower Carboniferous). It suggests heating of rocks (at temperatures from 60 to 110°C) in the area of high palaeogeothermal gradient, close to the Variscan front. In the Upper Devonian sequence of the Pągów IG 1 borehole, the CAI value of 4.5 proves heating of rock at a temperature exceeding 230°C as a result of higher heat flow near a fault zone. The low CAI values (1‒1.5) of Triassic rocks provide the evidence for heating of rocks in the range of 50 to 90°C. The relatively low maturity of organic matter in the Triassic rocks indicates that the Devonian and Carboniferous sediments must have reached their thermal maturity in the Late Carboniferous prior to the Variscan orogeny. The signs of crude oil and natural gas observed in the Devonian and Carboniferous rocks in the central part of the Małopolska Massif attest their potential for hydrocarbon exploration.
PL
W profilach otworów wiertniczych Pągów IG 1 i Węgrzynów IG 1 (centralna część masywu małopolskiego) wykonano badania konodontów z utworów węglanowych dewonu i najniższego karbonu. W profilu Węgrzynowa na podstawie konodontów udokumentowano utwory żywetu, franu i famenu datowane na poziomy dolny falsiovalis–górny postera, oraz turneju i wizenu z poziomów delicatus–texanus. W profilu Pągowa na podstawie konodontów udokumentowano fran i famen w zakresie poziomów jamieae–górny rhenana oraz dolny expansa. Niepełna sukcesja poziomów konodontowych w profilach Pągowa i Węgrzynowa wskazuje na obecność luk stratygraficznych. W Pągowie luki stwierdzono w utworach dewonu górnego oraz między utworami dewonu i karbonu, natomiast w Węgrzynowie w utworach z pogranicza dewonu i karbonu. W rejonie Węgrzynowa osady dewonu górnego były deponowane w zbiorniku o znacznie większej subsydencji niż w rejonie Pągowa. Utwory dewonu górnego masywu małopolskiego i obszarów ościennych odpowiadające zbliżonym przedziałom biostratygraficznym są podobne pod względem litologicznym i biofacjalnym.
EN
The conodont study was performed on Devonian and lowermost Carboniferous carbonate rocks from the Pągów IG 1 and Węgrzynów IG 1 boreholes located in the central part of the Małopolska Massif. Based on the conodont biostratigraphy, sediments assigned to the Givetian, Frasnian and Famennian (lower falsiovalis–upper postera zones) and to the Tournaisian and Visean (delicatus–texanus zones) were examined in the Węgrzynów section. The Pągów section is represented by Frasnian and Famennian sediments ascribed to the jamieae–upper rhenana and lower expansa zones. The incomplete conodont zone succession in the Pągów and Węgrzynów sections indicates the presence of stratigraphic gaps. In Pągów, these hiatuses were pinpointed in the Upper Devonian and between the Devonian and the Carboniferous, whereas in Węgrzynów at the Devonian–Carboniferous boundary. In the Węgrzynów area, deposition of the Upper Devonian sediments occurred in a basin, showing much greater subsidence than that in the Pągów area. In the Late Devonian sediments of the Małopolska Massif and neighbouring areas of much the same biostratigraphic intervals are similar in terms of lithologic and biofacies characteristics.
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.
EN
The only previous U-Pb zircon date for the the Early Carboniferous flysch sequence of the Moravo-Silesian Paleozoic Basin was published in 1987 from tuffogenic material from Kobylí Quarry at Krásné Loučky near the town of Krnov (Silesia, Czech Republic). The measured age of 319 Ma did not agree with its stratigraphic position, and was used as the basis for a hypothesized block of Late Carboniferous paralic molasse incorporated during a later tectonic event. During a survey of the still active quarry in 2010, volcaniclastic horizons were identified and sampled. Direct correspondence of the tuff units to those sampled in 1987 cannot be proved but is likely. High precision chemical abrasion - thermal ionization mass spectrometry (CA-TIMS) U-Pb dating of zircon from this new material has yielded an age of 340.05 ± 0.22 Ma, which correlates to the previously inferred stratigraphic age of the locality and the current calibration of the Early Carboniferous geologic time scale. The newly established age corresponds to the Visean stage and dates the boundary between the Horní Benešov and Moravice formations that can be correlated with other foredeep basins of the Culm in the European Variscides. A population of detrital Cambro-Ordovician zircons and a single 2.0 Ga old zircon crystal from the same volcaniclastic layer dated by laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) are consistent with the known age of source material in the Variscan orogenic front.
EN
The type collection of the lycopsid cone species Triplosporite brownii Unger was re-examined to assess its in situ spores. The cones are monosporangiate with only microspores that possess both cingulum and zona. They equate to the dispersed miospore genus Lycospora and would be identified as Lycospora cf. pseudoannulata. Therefore, the genus Triplosporite Brown is shown to be a junior synonym to Lepidostrobus and a species emendation is given. A comparison is given with the other Lepidostrobus cones which yielded similar in situ microspores of the Lycospora pellucida Group.
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