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Tytuł:
Litostratygrafia syluru polskiej części obniżenia perybałtyckiego - część lądowa i morska (N Polska)
The silurian lithostratigraphy of the Polish part of the Peri-Baltic Depression (N Poland)
Autorzy:
Modliński, Z.
Szymański, B.
Teller, L.
Powiązania:
https://bibliotekanauki.pl/articles/2074496.pdf
Data publikacji:
2006
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
sylur
litologia
litostratygrafia
palaeografia
Silurian
lithostratigraphic units
lithology
petrography
palaeogeography
Opis:
The Silurian rocks of the Peri-Baltic Depression area (N Poland) were penetrated by 208 boreholes (Fig. 1). Seven new formal lithostratigraphical units were recognized and defined: The Barciany Nodular Limestones Formation (Lower Llandoverian–Rhuddnian, Aeronian), the Pasłęk Bituminous Claystones Formation with the Jantar Bituminous Black Claystone Member (Llandoverian), the Pelplin Green Claystones Formation (Wenlockian–Ludlovian), the Kociewie Claystones and Siltstones Formation with the Reda Marly Siltstones Member (Wenlockian–Ludlovian) and the Puck Marly Claystones and Siltstones Formation (Ludlovian (Ludfordian)–Pridolian). Some of the units have a character of the allostratigraphical ones sensu „North American...”, (1983) because are bordered by the sedimentary or sedimentary-erosional unconformities. The lithology, stratigraphical position, thickness, paleontological data and spatial relation of the particular units are presented (Fig. 2). Their boundaries have been established and stratotypic sections are proposed. Rock sequences of different Formations have been correlated with lithostratigraphical and genetical equivalents of the adjacent regions of Lithuania and Russia (Kaliningrad District) and also with Denmark (Bornholm) and Germany (western part of the Peri-Baltic Depression).
Źródło:
Przegląd Geologiczny; 2006, 54, 9; 787-796
0033-2151
Pojawia się w:
Przegląd Geologiczny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Silurian stratigraphy of Central Iran - an update
Autorzy:
Hairapetian, V.
Ghobadi Pour, M.
Popov, L. E.
Männik, P.
Miller, C. G.
Powiązania:
https://bibliotekanauki.pl/articles/139183.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Iran
Silurian
biostratigraphy
lithostratigraphy
sedimentology
correlation
sylur
biostratygrafia
litostratygrafia
sedymentologia
korelacja
Opis:
The Silurian biostratigraphy, lithostratigraphy, and facies of Central Iran including the Kashmar (Boghu Mountains), Tabas (Derenjal Mountains, Ozbak-Kuh), Anarak (Pol-e Khavand) and Kerman regions is reviewed and updated. The current state of knowledge of the Silurian in the Zagros Basin, Alborz, Kopet-Dagh and Talysh regions, as well as in a few areas scattered across the Sabzevar Zone, and the Sanandaj-Sirjan terranes is also reviewed. Silurian volcanism in various parts of Iran is briefly discussed. The end of the Ordovician coincided with a widespread regression across Iran synchronous with the Hirnantian glaciation, and only in the Zagros Basin is there a continuous Ordovician–Silurian transition represented by graptolitic black shales of the Sarchahan Formation. In the Central-East Iranian Platform marine sedimentation re-commenced in the early to mid Aeronian. By the Sheinwoodian, carbonate platform depositional environments were established along its north-eastern margin. In other parts of Iran (e.g., Kopet-Dagh and the Sabzevar Zone), siliciclastic sedimentation continued probably into the late Silurian. The Silurian conodont and brachiopod biostratigraphy of Central Iran is significantly updated facilitating a precise correlation with the Standard Global Chronostratigraphic Scale, as well as with key Silurian sections in other parts of Iran. The Silurian lithostratigraphy is considerably revised and two new lithostratigraphical units, namely the Boghu and Dahaneh-Kalut formations, are introduced.
Źródło:
Acta Geologica Polonica; 2017, 67, 2; 201-233
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Upper Homerian (Silurian) high-resolution correlation using cyclostratigraphy: an example from western Lithuania
Autorzy:
Radzevičius, S.
Tumakovaitė, B.
Spiridonov, A.
Powiązania:
https://bibliotekanauki.pl/articles/139177.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Lithuania
Silurian
upper Homerian
cyclostratigraphy
graptolite biozones
Litwa
sylur
górny Homerian
cyklostratygrafia
Opis:
The Gėluva regional stage stratigraphically corresponds to the late Wenlock. This time interval witnessed significant graptolite extinctions and turnovers of conodont faunas, as well as a large positive Mulde carbon isotopic excursion. Thus, the development of a detailed stratigraphy is a necessary step in understanding the complex patterns of regional and global variations in the sediments accumulating during the time interval studied. Therefore, in this contribution we present a cyclostratigraphic analysis of gamma ray (GR) logs from four wells, which are located in the deep water facies belt of the Lithuanian part of the Silurian Baltic Basin of the Gėluva regional stage. The analysis was performed using REDFIT spectral estimation, continuous wavelet transform and signal filtering techniques. As a result two 4th order and five 5th order cycles were distinguished and named in all sections. The correlation of cycles between sections was calibrated with the graptolite biozones. The comparative analysis revealed that intra-basinal cyclostratigraphic correlation could achieve resolution of the order of several tens of thousands of years.
Źródło:
Acta Geologica Polonica; 2017, 67, 2; 307-322
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A review of Silurian fishes from north-western Hunan, China and related biostratigraphy
Autorzy:
Zhao, W. -J.
Zhu, M.
Gai, Z. -K.
Pan, Z. -H.
Cui, X. -D.
Cai, J. -C.
Powiązania:
https://bibliotekanauki.pl/articles/139181.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
early vertebrates
biostratigraphy
Silurian
north-western Hunan
China
kręgowce
biostratygrafia
sylur
Hunan
Chiny
Opis:
The Silurian fishes from north-western Hunan, China are characterised by the earliest known galeaspids Dayongaspis Pan and Zeng, 1985 and Konoceraspis Pan, 1992, and the earliest known antiarch Shimenolepis Wang J.-Q., 1991, as well as rich sinacanth fin spines. Shimenolepis from Lixian County in north-western Hunan, which was dated as the Telychian (late Llandovery), has long been regarded as the oldest representative of the placoderms in the world. As such, in addition to eastern Yunnan and the Lower Yangtze Region, north-western Hunan represents another important area in South China that yields important fossil material for the research of early vertebrates and related stratigraphy. Here we summarise the Silurian fishes known in north-western Hunan so far, and classify them into three vertebrate assemblages (i.e., the Wentang, Maoshan, and Yangtze assemblages). Based on the updated Silurian vertebrate and stratigraphic databases, the Silurian fish-bearing strata in north-western Hunan can be subdivided into the Rongxi, Huixingshao, and Xiaoxi formations in ascending chronological order, which can be correlated with the Lower Red Beds, the Upper Red Beds, and the Ludlow Red Beds in South China, respectively. A new look at the Silurian strata in Lixian suggests that the age of Shimenolepis is late Ludlow rather than late Llandovery as previously suggested. The research on Silurian fishes and biostratigraphy in north-western Hunan not only provides morphological data of early vertebrates, but also offers new palaeoichthyological evidence for the subdivision, correlation, and age assignment of the Silurian marine red beds in South China. The establishment of a related high-precision Silurian stratigraphic framework in north-western Hunan will help to elucidate the temporal and spatial distribution of Silurian fossil fishes, deepen the understanding of the evolution of early vertebrates, and unravel the coevolution between Silurian vertebrates and the palaeoenvironment.
Źródło:
Acta Geologica Polonica; 2018, 68, 3; 475-486
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Phanerozoic paleoenvironment and paleolithofacies maps : Early Paleozoic
Mapy paleośrodowiska i paleolitofacji fanerozoiku : wczesny paleozoik
Autorzy:
Golonka, J.
Powiązania:
https://bibliotekanauki.pl/articles/183797.pdf
Data publikacji:
2009
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
paleogeografia
kambr
ordowik
sylur
tektonika płyt litosfery
Cambrian
Ordovician
Silurian
plate tectonics
paleogeography
Opis:
The paper presents the detailed plate tectonic, paleogeographic, paleoenvironment and plaeolithofacies maps for eight Early Paleozoic time intervals. Forty maps, generated using PLATES and PALEOMAP programs, contain information about plate tectonics, paleoenvironment, and plaeolithofacies during Cambrian, Ordovician and Silurian. Disintegration of supercontinent Pannotia and origin of Gondwana, Laurentia and Baltica occur during Early Cambrian. Oceans spreading continued during Late Cambrian and Early Ordovician; vast platform flooded by shallow seas existed on the continents. The plate tectonic reorganization happened during Middle Ordovician. Silurian was a time of Caledonian orogeny, closing of Early Paleozoic oceans and origin of supercontinent Laurussia as a result of Laurentia and Baltica collision. Information contained within global and regional papers were posted on the maps and the detailed paleoenvironment and plaeolithofacies zones were distinguished within the platforms, basins and ridges.
Artykuł przedstawia szczegółowe mapy paleogeograficzne dla ośmiu przedziałów czasowych w obrębie wczesnego paleozoiku. Czterdzieści map, skonstruowanych przy użyciu programów PLATES i PALEOMAP, zawiera informacje dotyczące tektoniki płyt, paleośrodowiska i paleolitofacji w czasie kambru, ordowiku i syluru. We wczesnym kambrze nastąpił rozpad superkontynentu Pannotia i utworzyły się kontynenty: Gondwana, Laurencja, Bałtyka i Syberia. W późnym kambrze i wczesnym ordowiku w dalszym ciągu ma miejsce spreding oceanów, istnieją też w tym czasie rozległe platformy zalane przez płytkie morza na kontynentach. Reorganizacja płyt litosfery nastąpiła w środkowym ordowiku. Sylur był okresem orogenezy kaledońskiej, zamknięciem wczesno- paleozoicznych oceanów i powstania superkontynentu Laurosji z połączenia Laurencji i Bałtyki. Informacje zawarte w szeregu globalnych i regionalnych prac zostały naniesione na mapy, a w obrębie platform, basenów i grzbietów wydzielono poszczególne strefy paleośrodowiskowe i paleolitofacjalne
Źródło:
Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie; 2009, 35, 4; 589-654
0138-0974
Pojawia się w:
Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stromatoporoid beds and flat-pebble conglomerates interpreted as tsunami deposits in the Upper Silurian of Podolia, Ukraine
Autorzy:
Łuczyński, P.
Skompski, S.
Kozłowski, W.
Powiązania:
https://bibliotekanauki.pl/articles/138749.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Palaeotsunami
Silurian
Podolia
Stromatoporoid beds
Flat-pebble conglomerates
sylur
Podole
warstwy stromatoporoidowe
prefabrykaty płaskie
Opis:
Tsunami deposits are currently a subject of intensive studies. Tsunamis must have occurred in the geological past in the same frequency as nowadays, yet their identified depositional record is surprisingly scarce. Here we describe a hitherto unrecognized example of probable palaeotsunamites. The Upper Silurian (Pridoli) carbonate succession of Podolia (southwestern Ukraine) contains variously developed event beds forming intercalations within peritidal deposits (shallow water limestones, nodular marls and dolomites). The event beds are represented by stromatoporoid and fine-grained bioclastic limestones, in some places accompanied by flat-pebble conglomerates. The interval with event beds can be traced along the Zbruch River in separate outcrops over a distance of more than 20 km along a transect oblique to the palaeoshoreline. The stromatoporoid beds have erosional bottom surfaces and are composed of overturned and often fragmented massive skeletons. The material has been transported landward from their offshore habitats and deposited in lagoonal settings. The flat-pebble conglomerates are composed of sub-angular micritic clasts that are lithologically identical to the sediments forming the underlying beds. Large-scale landward transport of the biogenic material has to be attributed to phenomena with very high energy levels, such as tropical hurricanes or tsunamis. This paper presents a tsunamigenic interpretation. Morphometric features of redeposited stromatoporoids point to a calm original growth environment at depths well below storm wave base. Tsunami waves are the most probable factor that could cause their redeposition from such a setting. The vastness of the area covered by parabiostromal stromatoporoid beds resembles the distribution of modern tsunami deposits in offshore settings. The stromatoporoid beds with unsorted stromatoporoids of various dimensions evenly distributed throughout the thickness of the beds and with clast-supported textures most probably represent deposition by traction. In some sections, the stromatoporoids are restricted to the lowermost parts of the beds, which pass upwards into bioclastic limestones. In this case, the finer material was deposited from suspension. The coexistence of stromatoporoid beds and flat-pebble conglomerates also allows presenting a tsunami interpretation of the latter. The propagating tsunami waves, led to erosion of partly lithified thin-layered mudstones, their fragmentation into flat clasts and redeposition as flat-pebble conglomerates.
Źródło:
Acta Geologica Polonica; 2014, 64, 3; 261-280
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Waloryzacja geostanowisk na obszarze projektowanego Geoparku Łysogórskiego w Górach Świętokrzyskich
Valorization of geosites in the projected Łysogóry Geopark in the Holy Cross Mountains
Autorzy:
Fijałkowska-Mader, A.
Malec, J.
Powiązania:
https://bibliotekanauki.pl/articles/2075050.pdf
Data publikacji:
2013
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Cambrian
Silurian
Devonian
Cenozoic
geosite
geodiversity
geotourism
kambr
sylur
devon
kenozoik
geostanowisko
georóżnorodność
geoturystyka
Opis:
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.
Źródło:
Przegląd Geologiczny; 2013, 61, 3; 165--171
0033-2151
Pojawia się w:
Przegląd Geologiczny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Łupki sylurskie platformy wschodnioeuropejskiej w Polsce : wybrane problemy poszukiwawcze
Silurian shales of the East European Platform in Poland : some exploration problems
Autorzy:
Porębski, S.J.
Prugar, W.
Zacharski, J.
Powiązania:
https://bibliotekanauki.pl/articles/2075081.pdf
Data publikacji:
2013
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Silurian
black shale
shale gas
unconventional play
sylur
ciemne łupki
gaz łupkowy
niekonwencjonalna gra
Opis:
The pericratonic Silurian shale succession in Poland, despite its reasonably well-constrained geological framework, entails a number of contentious issues that need to be resolved before this emerging shale gas play will enter a stage of successful development. The succession is thought to have originated in a Caledonian foredeep encroaching distally onto a pericratonic shelf ramp. However, the geochemical signature of the mudrocks is consistent with a cratonic rather than orogenic sourcing, the proximal part of the foredeep basin-fill is apparently missing, and the shale succession juxtaposes in part across the Teisseyre-Tornquist Zone against suspected ter- ranes with no evidence of Silurian tectonism. Organic-rich Llandovery-Wenlock shales form a NW-SE striking central belt that is increasingly calcareous toward the craton (NE) and more silty toward the inferred orogen (SW), with the TOC content decreasing in both directions perpendicular to the strike. The TOC trend seems consistent with the deep-downlap model of black shale deposition suggested for many Paleozoic foredeep basins, but does not quite agree with the outer neritic to upper bathyal depths assumed for the shale deposition. Preliminary results from three wells drilled by Orlen Upstream in the Lublin Basin indicate that the Llandovery-Wenlock shales were deposited on a distal shelf ramp sheltered from the craton by shelf carbonate shoals and periodically affected by weak storm-generated currents. The impact of storms on water column resulted in intermittent rises of oxygen content in the otherwise anoxic to dysoxic near-bottom conditions. The prospective interval is dominated by calcite-cemented clayey mudstones showing moderate to good reservoir qualities. It is cut locally by ENE- or NE-dipping, steep fractures favourable for fluid transmissibility, and a NE or SW direction is most advantageous for artificial fracturing. This interval is capped with a Ludlow calcite-cemented, laminated siltstone that forms a regional correlation marker and shows soft-sediment deformations attributable to gravitational collapse on a NE-dippingpaleoslope. If correct, this interpretation might imply the encroachment of orogen-fed clinothem system onto the SW-inclined craton-margin shelf ramp.
Źródło:
Przegląd Geologiczny; 2013, 61, 8; 468--477
0033-2151
Pojawia się w:
Przegląd Geologiczny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nowelizacja stratygrafii syluru w wybranych profilach wiertniczych obniżenia bałtyckiego (Polska północna)
Revision of the Silurian stratigraphy in selected boreholes from the Polish sector of the Baltic Depression (northern Poland)
Autorzy:
Szymański, B.
Modliński, Z.
Powiązania:
https://bibliotekanauki.pl/articles/2063391.pdf
Data publikacji:
2003
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
stratygrafia
graptolity
sylur
obniżenie bałtyckie
Polska Północna
graptolites
stratigraphy
Silurian
Baltic Depression
northern Poland
Opis:
Zaprezentowano wyniki rewizji podziału graptolitowego serii sylurskiej w wybranych profilach wiertniczych polskiej części obniżenia bałtyckiego. Dotychczasowy podział był oparty na autorskim schemacie E. i H. Tomczyków (1962-1990), który zawiera szereg błędnych rozwiązań. Zakres proponowanych korekt obejmuje m.in.: ujednolicenie granic systemu, dolnej - ordowik/sylur i górnej - sylur/dewon, eliminację jednostek rangi oddziału określanych jako siedlce i podlasie, zdefiniowanie granic i zasięgów standardowych oddziałów systemu (landower, wenlok, ludlow, pridoli) oraz pięter (gorst i ludford), wreszcie rezygnację z szeregu wyróżnianych dotychczas regionalnych poziomów graptolitowych. Niektóre z nich nie mają wszystkich cech umożliwiających ich identyfikację na obszarze całego basenu. Dla innych niemożliwe jest udokumentowanie ich granic i zasięgów. Jeszcze inne są niedostatecznie udokumentowane, co uniemożliwia jednoznaczne korelacje ze standardowymi poziomami graptolitowymi skali globalnej. Zmodyfikowany schemat podziału serii sylurskiej ilustrują profile otworów wiertniczych: Słupsk IG 1, Lębork IG 1, Kościerzyna IG 1, Żarnowiec IG 1, Gdańsk IG 1, Hel IG 1, Pasłęk IG 1 i Bartoszyce IG 1.
This study revises the graptolite zonation of the Silurian System in selected boreholes from the Polish sector of the Baltic Depression. The previous zonation was based on the scheme by Tomczykowa & Tomczyk (1962-1990) and contained many errors. The revision resulted in, among others, unification of the basal and top boundaries of the Silurian System, elimination of the Siedlce series and Podlasie series, determination of limits and ranges of the standard Series (Llandovery, Wenlock, Ludlow and Pridoli) and Stages (Gorstian and Ludfordian), and relinquishment of several regional graptolite zones. Some of the zones do not posses enough attributes to allow their identification across the entire basin. For others it is impossible to dating their limits and ranges. Yet others are insufficiently documented, that makes them impossible to correlate with the standard graptolite zones. The modified stratigraphic scheme of the Silurian System is illustrated by borehole sections: Słupsk IG 1, Lębork IG 1, Kościerzyna IG 1, Żarnowiec IG 1, Gdańsk IG 1, Hel IG 1, Pasłęk IG 1 and Bartoszyce IG 1.
Źródło:
Biuletyn Państwowego Instytutu Geologicznego; 2003, 405; 109--138
0867-6143
Pojawia się w:
Biuletyn Państwowego Instytutu Geologicznego
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Do the available data permit clarification of the possible dependence of Palaeozoic brachiopod generic diversity dynamics on global sea-level changes? A viewpoint
Autorzy:
Ruban, D. A.
Powiązania:
https://bibliotekanauki.pl/articles/94246.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet im. Adama Mickiewicza w Poznaniu
Tematy:
brachiopods
generic diversity
sea-level changes
Silurian
Devonian
ramienionogi
zmiany poziomu morza
sylur
dewon
Opis:
At a glance, progress in palaeontology and eustatic reconstructions in the past decade permits to prove or to disprove the possible dependence of Palaeozoic brachiopod generic diversity dynamics on global sea-level changes. However, the available diversity curve is of much lower resolution than the eustatic curve. This problem can be resolved by decreasing the resolution of the latter. The other restriction linked to the chronostratigraphical incompatibility of the available data allows to focus on the Middle Palaeozoic only. A series of mass extinctions and other biotic crises in the Silurian-Devonian does not allow to interpret correctly the results of direct comparison of the brachiopod generic diversity dynamics with global sea-level changes. With the available data, it is only possible to hypothesize that the eustatic control was not playing a major part in diversity dynamics of Middle Palaeozoic brachiopods. The resolution of the stratigraphic ranges of Palaeozoic brachiopods should be increased significantly, and these ranges should be plotted against the most up-to-date geologic time scale. Until this task will be achieved, it is impossible to judge about the existence of any dependence (either full or partial) of the Palaeozoic brachiopod diversity dynamics on global sea-level changes.
Źródło:
Geologos; 2014, 20, 3; 215-221
1426-8981
2080-6574
Pojawia się w:
Geologos
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The use of X-ray computed microtomography for graptolite detection in rock based on core internal structure visualization
Autorzy:
Kaczmarek, Ł.
Kozłowska, A.
Maksimczuk, M.
Wejrzanowski, T.
Powiązania:
https://bibliotekanauki.pl/articles/139097.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
computed microtomography
visualization
graptolites
Silurian
Baltic Basin shale
mikrotomografia komputerowa
wizualizacja
graptolity
sylur
łupki basenu bałtyckiego
Opis:
This paper presents for the first time X-ray computed microtomography (μCT) analysis as a technique for Silurian graptolite detection in rocks. The samples come from the Jantar Bituminous Claystones Member of the Opalino core, Baltic Basin, northern Poland. Images were obtained with spatial resolution of 25 μm, which enabled the authors to create a 3-D visualization and to calculate the ratio of fissure and graptolite volume to the total sample volume. A set of μCT slices was used to create a 3-D reconstruction of graptolite geometry. These μCT slices were processed to obtain a clearly visible image and the volume ratio. A copper X-ray source filter was used during exposure to reduce radiograph artifacts. Visualization of graptolite tubaria (rhabdosomes) enabled Demirastrites simulans to be identified. Numerical models of graptolites reveal promising applications for paleontological research and thus for the recognition and characterization of reservoir rocks.
Źródło:
Acta Geologica Polonica; 2017, 67, 2; 299-306
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Coexistence of algae and a graptolite-like problematicum: a case study from the late Silurian of Podolia (Ukraine)
Autorzy:
Skompski, Stanisław
Kozłowski, Wojciech
Łuczyński, Piotr
Kozłowska, Anna
Powiązania:
https://bibliotekanauki.pl/articles/27323966.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
Dasycladales
Graptolite-like epibionts
Silurian
Ludlow
Ukraine
periti dal environment
glony
graptolity
epibionty
sylur
ludlow
Ukraina
Opis:
This contribution presents the record of an abundant assemblage of well-preserved, thallophytic noncalcified algae and of an epibiotic form that has been recognised as a putative graptolite from the upper Silurian (Ludlow, Gorstian–Ludfordian) of Podolia (western part of Ukraine). The sediments represent a shallow peritidal zone of the shelf. A new genus and species, Voronocladus dryganti, belonging to the Dasycladales Pascher, 1931, is established. Most of the specimens representing the algal thallus are overgrown by problematical epibiotic graptolites, described as Podoliagraptus algaeoides gen. et sp. nov. This phenomenon is explained as an epiphytic mode of life of the putative graptolite on algae, and is herein compared to recently known coexistences of algae with other organisms. The excellent state of preservation, and the abundance of studied Dasycladales algae and epibiotic problematics indicate that the investigated mudstone layer can be treated as a ‘Konservat Lagerstätte’ sensu Seilacher (1970).
Źródło:
Acta Geologica Polonica; 2023, 73, 2; 115--133
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Graptolity : narzędzie stratygraficzne w rozpoznaniu stref perspektywicznych dla występowania niekonwencjonalnych złóż węglowodorów
Graptolites : stratigraphic tool in the exploration of zones prospective for the occurrence of unconventional hydrocarbon deposits
Autorzy:
Podhalańska, T.
Powiązania:
https://bibliotekanauki.pl/articles/2075084.pdf
Data publikacji:
2013
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
graptolites
black shale
stratigraphy
Ordovician
Silurian
East European Craton
graptolity
ciemne łupki
stratygrafia
ordowik
sylur
platforma wschodnioeuropejska
Opis:
In connection with the exploration of zones prospective for the occurrence of unconventional hydrocarbon deposits, numerous studies of source rocks have been conducted in Poland. Stratigraphic examinations are among the basic elements. The main group of fossils occurring in shale successions, being a potential source of hydrocarbons, is graptolites. This paper describes the assemblages of graptolites from Ordovician and Silurian deposits and shows their importance for the stratigraphy of shale complexes. Due to their abundance and rapid evolution, graptolites are an excellent tool for biostratigraphic dating, regional correlations and biozonation of rock successions in terms of the high-resolution sequence stratigraphy. The paper presents the significance of taphonomic research of graptolites to identify zones of increased accumulation of hydrocarbons in rocks. It has been found that graptolites are an equally important instrument, in addition to elevated TOC values or increased gamma ray radiation on well logs, that allows identification of potential source rocks for hydrocarbons, including shale gas.
Źródło:
Przegląd Geologiczny; 2013, 61, 8; 460--467
0033-2151
Pojawia się w:
Przegląd Geologiczny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Regressive-transgressive cyclothem with facies record of the re-flooding window in the Late Silurian carbonate succession (Podolia, Ukraine)
Autorzy:
Łuczyński, P.
Kozłowski, W.
Skompski, S.
Powiązania:
https://bibliotekanauki.pl/articles/138684.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
re-flooding window
spectral gamma ray record
shallow water carbonates
late Silurian
Podolia
wody płytkie
węglan
sylur
Podole
Opis:
The term “re-flooding window” was recently proposed as a time-interval connected with the transgressive stage of present day peri-reefal development. In the analysis presented here, a fossil record of a re-flooding window has been recognized. Nine Late Silurian carbonate sections exposed on the banks of the Dnister River in Podolia (Ukraine) have been correlated base on bed-by-bed microfacies analysis and spectral gamma ray (SGR) measurements. Correlated were sections representing settings ranging from the inner part of a shallow-water carbonate platform to its slope, through an organic buildup. The reconstructed depositional scenario has been divided into six development stages, with the first three representing a regressive interval and the latter three a transgressive interval of the basin’s history. The re-flooding window has been identified at the beginning of a transgressive part of the succession. Surprisingly, it is characterized by an extremely fast growth of a shallow, tide-dominated platform and by deposition of calciturbiditic layers in a more basinal area. The interpreted succession is a small-scale model illustrating the reaction of carbonate depositional sub-environments to sea level changes and determining the facies position of the stromatoporoid buildups within the facies pattern on a Silurian shelf. The use of SGR analyses in shallow water, partly high-energy, carbonate facies, both for correlation purposes and for identifying depositional systems, is a relatively new method, and thus can serve as a reference for other studies of similar facies assortment.
Źródło:
Acta Geologica Polonica; 2015, 65, 3; 297-318
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Palaeo-earthquake events during the late Early Palaeozoic in the central Tarim Basin (NW China): evidence from deep drilling cores
Autorzy:
He, B.
Qiao, X.
Jiao, C.
Xu, Z.
Cai, Z.
Guo, X.
Zhang, Y.
Powiązania:
https://bibliotekanauki.pl/articles/94300.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet im. Adama Mickiewicza w Poznaniu
Tematy:
soft-sediment deformation structures
seismites
palaeo-seismicity
Late Ordovician
Silurian
Tazhong 1 Fault
Tarim Basin
struktury deformacji
osady miękkie
sejsmity
ordowik późny
sylur
Kotlina Kaszgarska
Opis:
Various millimetre-, centimetre- and metre-scale soft-sediment deformation structures (SSDS) have been identified in the Upper Ordovician and Lower-Middle Silurian from deep drilling cores in the Tarim Basin (NW China). These structures include liquefied-sand veins, liquefaction-induced breccias, boudinage-like structures, load and diapir- or flame-like structures, dish and mixed-layer structures, hydroplastic convolutions and seismic unconformities. The deformed layers are intercalated by undeformed layers of varying thicknesses that are petrologically and sedimentologically similar to the deformed layers. The SSDS developed in a shelf environment during the early Late Ordovician and formed initially under shear tensile stress conditions, as indicated by boudinage-like structures; during the latest Ordovician, SSDS formed under a compressional regime. The SSDS in the Lower-Middle Silurian consist mainly of mixed layers and sand veins; they formed in shoreline and tidal-flat settings with liquefaction features indicating an origin under a compressional stress regime. By Silurian times, the centre of tectonic activity had shifted to the south-eastern part of the basin. The SSDS occur at different depths in wells that are close to the syn-sedimentary Tazhong 1 Fault (TZ1F) and associated reversed-thrust secondary faults. Based on their characteristics, the inferred formation mechanism and the spatial association with faults, the SSDS are interpreted as seismites. The Tazhong 1 fault was a seismogenic fault during the later Ordovician, whereas the reversed-direction secondary faults became active in the Early-Middle Silurian. Multiple palaeo-earthquake records reflect pulses and cyclicity, which supports secondary tectonic activity within the main tectonic movement. The range of SSDS structures reflects different developments of tectonic activity with time for the various tectonic units of the centralbasin. The effects of the strong palaeo-earthquake activity coincide with uplift, fault activity and syn-tectonic sedimentation in the study area during the Late Ordovician to Middle Silurian.
Źródło:
Geologos; 2014, 20, 2; 105-123
1426-8981
2080-6574
Pojawia się w:
Geologos
Dostawca treści:
Biblioteka Nauki
Artykuł

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