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Tytuł:
The brachiopod succession through the Silurian–Devonian boundary beds at Dnistrove, Podolia, Ukraine
Autorzy:
Balinski, A.
Powiązania:
https://bibliotekanauki.pl/articles/23447.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
brachiopod
succession
Silurian
Devonian
boundary bed
Podolia
Ukraine
Brachiopoda
paleontology
paleoenvironment
Opis:
In the classic section across the Silurian–Devonian boundary at Dnistrove (Podolia, Ukraine) the brachiopod fauna has never been studied in detail. This paper presents results of research on brachiopods from this important locality and time interval. Bed−by−bed collecting has enabled the detailed distribution of brachiopod taxa through the boundary beds to be revealed. Generally, the reference section at Dnistrove yields rather scarce but often well preserved brachiopods. Dayia bohemica and Dnestrina gutta can be regarded as characteristic species for the uppermost Silurian. A relatively high−diversity but low−abundance brachiopod fauna occurs in the lowest 1.8 m of the earliest Devonian. Only three forms have been found to cross the Silurian–Devonian boundary: the strophomenide Plectodonta (Plectodonta) mariae pantherae subsp. nov., the atrypide Gracianella (Sublepida) paulula sp. nov., and the spiriferide Howellella (Howellella) latisinuata. A relatively narrow brachiopod−rich interval at 5.5 m above the Silurian–Devonian boundary yields 16 brachiopod species which probably indicate a setting near the lower limit of the photic zone equivalent to the Benthic Assemblage 3–4 boundary. Two new species and one new subspecies are described: Skenidioides tatyanae, Plectodonta (Plectodonta) mariae pantherae, and Gracianella (Sublepida) paulula.
Źródło:
Acta Palaeontologica Polonica; 2012, 57, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Upper Silurian to Middle Devonian conodont faunas from the Rabat-Tiflet area (northwestern Moroccan Meseta)
Autorzy:
Benfrika, El.M.
Bultynck, P.
El Hassani, A.
Powiązania:
https://bibliotekanauki.pl/articles/2059519.pdf
Data publikacji:
2007
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Morocco
Meseta
biostratigraphy
Pridoli-middle Givetian
conodonts
Opis:
Conodont faunas are generally sparse in Pridolito middle Givetian deposits from the Rabat-Tiflet area in the north western Moroccan Meseta. The Pridoli and Lochkovian rocks consist of dark platy limestones alternating with dark shales containing graptolites in some levels. In the over lying part of the succession carbonate rocks predominate with the development of reefoid limestones in the lower Givetian. The eosteinhornensis, sulcatus, dehiscens vel kitabicus, laticostatus/inversus, partitus, ensensis, hemiansatus, timorensis and rhenanus/varcus zones have been recognized by occurrence of the conodont in dexspecies.The first appearance of Belodella devonica, occurring together with the graptolite Monograptus uniformis is used as a regional index species for the base of the Devonian. The age of some levels in the succession were previously dated by graptolites, dacryoconarids and rare goniatites.
Źródło:
Geological Quarterly; 2007, 51, 4; 393-406
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Facies transition and biostratigraphic correlation of the Upper Silurian and Lower Devonian in West Bulgaria
Autorzy:
Boncheva, I.
Sachanski, V.
Lakova, I.
Yaneva, M.
Powiązania:
https://bibliotekanauki.pl/articles/2059515.pdf
Data publikacji:
2007
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Bulgaria
Upper Silurian-Lower Devonian
conodonts
graptolites
facies transition
Opis:
Upper Silurian and Lower Devonian shelf deposits in West Bulgaria are exposed in three main Alpine tectonic units: the West Balkan Unit, the Lyubash Monocline and the Morava Unit. The West Balkan and Lyubash units consist of siliciclastic deposits: black graptolitic shales, banded pale shales and black siltstones. The Ludlow, Pridoli, Lochkovian, Pragian and Emsian were recognized on the basis of graptolite and tentaculite faunas. In the Morava Unit, the Ludlow black shales are progressively replaced by clayey limestones and nodular and micritic limestones in the Pridoli and Early Devonian. Newly obtained conodonts show the presence of the siluricus, eosteinhornensis, woschmidti, postwoschmidti, delta-pesavis, sulcatus, dehiscens and gronbergi zones. Petrographic study of the Morava Unit shows an increasing carbonate content and shallowing conditions upwards. The biostratigraphical correlation and facies interpretation reveal the coeval existence of two different depositional environments within the same shelf basin as well as a gradual shift in proximal direction.
Źródło:
Geological Quarterly; 2007, 51, 4; 407-418
1641-7291
Pojawia się w:
Geological Quarterly
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:
Tentaculites of the Upper Silurian and Lower Devonian of Poland
Tentakulity górnego syluru i dolnego dewonu Polski
Tentakulity verkhnego silura i nizhnego devona Polshi
Autorzy:
Hajlasz, B.
Powiązania:
https://bibliotekanauki.pl/articles/23098.pdf
Data publikacji:
1974
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Źródło:
Acta Palaeontologica Polonica; 1974, 19, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Interrelations between stromatoporoid morphometric features - a quantitative approach based on specimens from the Silurian of Podolia (Ukraine) and the Devonian of the Holy Cross Mountains (Poland)
Autorzy:
Łuczyński, Piotr
Powiązania:
https://bibliotekanauki.pl/articles/1835590.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
stromatoporoids
Morphometric features
quantitative analysis
palaeoenvironmental interpretation
clogging
Stromatoporoidy
analiza ilościowa
kolmatacja
Opis:
Morphometric attributes of 705 stromatoporoid specimens from a number of exposures from the Silurian of Podolia (Ukraine) and the Devonian of the Holy Cross Mountains (Poland), representing a wide array of shallow water carbonate sedimentary environments, have been analysed. Taken into account were such parameters as: general shape of the skeleton, shape of the final growth form (living surface profile), upper surface character, latilaminae arrangement, burial ratio and type of initial surface. A number of new ratios has been introduced, designed mainly to improve the mapping of the outlines of the stromatoporoids upper surfaces. All studied specimens were treated as belonging to one group, and relations between particular attributes were tested. The results were analysed in terms of potential environmental factors influencing stromatoporoid morphometric features. Most of the distinguished attributes are common in the studied group and occur in various combinations, with an important exception of parameters designed to reflect the shape of the skeleton’s upper surface, which are distinctly predominated by convex variants. This indicates that surface concavity was a highly undesired feature among stromatoporoids. Upper surface convexity is interpreted herein as a response to the hazard of clogging of the animals pores by tiny sediment particles suspended in the bottom turbid water layer. Common low burial ratios of final living surface profiles and the occurrence of specimens with a smooth upper surface but a non-enveloping latilaminae arrangement are other reflections of this phenomenon. Burial by sediments and redeposition were also important factors governing stromatoporoid development. No direct arguments indicating photosensitivity of stromatoporoids can be deduced from the presented results. The hitherto postulated allometric tendency among stromatoporoids of starting growth as laminar forms and later adopting consecutively higher profile shapes has not been confirmed here. On the contrary, a tendency for gradual elimination of very high profile forms with increasing stromatoporoid size has been observed. The final shape of a stromatoporoid skeleton was always an effect of a combination of various agents.
Źródło:
Acta Geologica Polonica; 2020, 70, 3; 311-337
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Interrelations between stromatoporoid morphometric features - a quantitative approach based on specimens from the Silurian of Podolia (Ukraine) and the Devonian of the Holy Cross Mountains (Poland)
Autorzy:
Łuczyński, Piotr
Powiązania:
https://bibliotekanauki.pl/articles/24024718.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
stromatoporoids
morphometric features
quantitative analysis
palaeoenvironmental interpretation
clogging
stromatoporoidy
morfometria
analiza ilościowa
interpretacja paleośrodowiskowa
kolmatacja
Opis:
Morphometric attributes of 705 stromatoporoid specimens from a number of exposures from the Silurian of Podolia (Ukraine) and the Devonian of the Holy Cross Mountains (Poland), representing a wide array of shallow water carbonate sedimentary environments, have been analysed. Taken into account were such parameters as: general shape of the skeleton, shape of the final growth form (living surface profile), upper surface character, latilaminae arrangement, burial ratio and type of initial surface. A number of new ratios has been introduced, designed mainly to improve the mapping of the outlines of the stromatoporoids upper surfaces. All studied specimens were treated as belonging to one group, and relations between particular attributes were tested. The results were analysed in terms of potential environmental factors influencing stromatoporoid morphometric features. Most of the distinguished attributes are common in the studied group and occur in various combinations, with an important exception of parameters designed to reflect the shape of the skeleton’s upper surface, which are distinctly predominated by convex variants. This indicates that surface concavity was a highly undesired feature among stromatoporoids. Upper surface convexity is interpreted herein as a response to the hazard of clogging of the animals pores by tiny sediment particles suspended in the bottom turbid water layer. Common low burial ratios of final living surface profiles and the occurrence of specimens with a smooth upper surface but a non-enveloping latilaminae arrangement are other reflections of this phenomenon. Burial by sediments and redeposition were also important factors governing stromatoporoid development. No direct arguments indicating photosensitivity of stromatoporoids can be deduced from the presented results. The hitherto postulated allometric tendency among stromatoporoids of starting growth as laminar forms and later adopting consecutively higher profile shapes has not been confirmed here. On the contrary, a tendency for gradual elimination of very high profile forms with increasing stromatoporoid size has been observed. The final shape of a stromatoporoid skeleton was always an effect of a combination of various agents.
Źródło:
Acta Geologica Polonica; 2020, 70, 3; 311--337
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Interrelations between stromatoporoid morphometric features - a quantitative approach based on specimens from the Silurian of Podolia (Ukraine) and the Devonian of the Holy Cross Mountains (Poland)
Autorzy:
Łuczyński, Piotr
Powiązania:
https://bibliotekanauki.pl/articles/138828.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
stromatoporoids
Morphometric features
quantitative analysis
palaeoenvironmental interpretation
clogging
Stromatoporoidy
analiza ilościowa
kolmatacja
Opis:
Morphometric attributes of 705 stromatoporoid specimens from a number of exposures from the Silurian of Podolia (Ukraine) and the Devonian of the Holy Cross Mountains (Poland), representing a wide array of shallow water carbonate sedimentary environments, have been analysed. Taken into account were such parameters as: general shape of the skeleton, shape of the final growth form (living surface profile), upper surface character, latilaminae arrangement, burial ratio and type of initial surface. A number of new ratios has been introduced, designed mainly to improve the mapping of the outlines of the stromatoporoids upper surfaces. All studied specimens were treated as belonging to one group, and relations between particular attributes were tested. The results were analysed in terms of potential environmental factors influencing stromatoporoid morphometric features. Most of the distinguished attributes are common in the studied group and occur in various combinations, with an important exception of parameters designed to reflect the shape of the skeleton’s upper surface, which are distinctly predominated by convex variants. This indicates that surface concavity was a highly undesired feature among stromatoporoids. Upper surface convexity is interpreted herein as a response to the hazard of clogging of the animals pores by tiny sediment particles suspended in the bottom turbid water layer. Common low burial ratios of final living surface profiles and the occurrence of specimens with a smooth upper surface but a non-enveloping latilaminae arrangement are other reflections of this phenomenon. Burial by sediments and redeposition were also important factors governing stromatoporoid development. No direct arguments indicating photosensitivity of stromatoporoids can be deduced from the presented results. The hitherto postulated allometric tendency among stromatoporoids of starting growth as laminar forms and later adopting consecutively higher profile shapes has not been confirmed here. On the contrary, a tendency for gradual elimination of very high profile forms with increasing stromatoporoid size has been observed. The final shape of a stromatoporoid skeleton was always an effect of a combination of various agents.
Źródło:
Acta Geologica Polonica; 2020, 70, 3; 311-337
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sedimentology of deposits from around the Late Caledonian unconformity in the western Holy Cross Mts.
Autorzy:
Malec, J.
Powiązania:
https://bibliotekanauki.pl/articles/2059319.pdf
Data publikacji:
2001
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Holy Cross Mountains
Upper Silurian-Lower Devonian
stratigraphy
sedimentology
Late Caledonian unconformity
Opis:
The Upper Silurian-Lower Devonian section of the western part of the Holy Cross Mts. is composed of greywackes of the Niewachlów Beds, Kielce Beds and Miedziana Góra Conglomerates. They are separated from the terrestrial Gruchawka Conglomerates and Barcza Beds by an erosional surface. Depositional structures recorded in the Silurian greywackes indicate the deep-water sedimentary environment of a flysch facies. The uppermost part of the Kielce Beds and the Miedziana Góra Conglomerates accumulated on a submarine delta fan. These deposits correspond to Late Caledonian molasse and are associated with closure of the Late Silurian basin in the Holy Cross Mts. The Gruchawka Conglomerates, containing fish remains, mark the beginning of the Early Devonian marine transgression. Together with the overlying sandstones and mudstones of the Barcza Beds they form the Old Red Sandstone succession. The Late Caledonian unconformity occurs between the Upper Silurian molasse deposits and Lower Devonian Old Red Sandstone facies, and the stratigraphic gap most likely spans the Pridoli, Lochkovian and lower Pragian. Large thicknesses of Silurian greywackes in the NW part of Kielce, and the high degree of thermal maturity of organic matter, indicate a geotectonic affinity of this region with the Łysogóry Block.
Źródło:
Geological Quarterly; 2001, 45, 4; 397-416
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Faunal dynamics across the Silurian-Devonian positive isotope excursions (delta13C, delta18O) in Podolia, Ukraine: Comparative analysis of the Ireviken and Klonk events
Autorzy:
Racki, G.
Balinski, A.
Wrona, R.
Malkowski, K.
Drygant, D.
Szaniawski, H.
Powiązania:
https://bibliotekanauki.pl/articles/20924.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
fauna dynamics
Silurian
Devonian
isotope excursion
Podolia
Ukraine
comparative analysis
Ireviken event
Klonk event
Brachiopoda
Conodonta
Chitinozoa
carbon isotope
oxygen isotope
geochemistry
Opis:
Two global isotopic events, the early Sheinwoodian (early Wenlock) and that at the Silurian–Devonian transition, have been comprehensively studied in representative carbonate successions at Kytayhorod and Dnistrove, respectively, in Podolia, Ukraine, to compare geochemistry and biotic changes related correspondingly to the Ireviken and Klonk events. These two large−scale isotope excursions reveal different regional ecosystem tendencies. The well−defined increasing trend across the Llandovery–Wenlock boundary in siliciclastic input, redox states and, supposedly, bioproductivity, was without strict correlative relations to the major ¹³C enrichment event. The environmental and biotic evolution was forced by eustatic sea−level fluctuations and two−step climate change toward a glaciation episode, but strongly modified by regional epeirogeny movements due to location near the mobile Teisseyre−Törnquist Fault Zone. Thus, the global early Sheinwoodian biogeochemical perturbation was of minor depositional significance in this epeiric sea, as in many other Laurussian domains. Conversely, the Podolian sedimentary record of the Klonk Event exhibits temporal links to the abrupt δ¹³C anomaly, overprinted by a tectonically driven deepening pulse in the crucial S–D boundary interval. This carbon cycling turnover was reflected in the regional carbonate crisis and cooling episodes, paired with a tendency towards eutrophication and recurrent oxygen deficiency, but also with major storms and possible upwelling. Faunal responses in both Podolian sections follow some characters of the Silurian pattern worldwide, as manifested by conodont changeover prior to the major early Sheinwoodian isotopic/climatic anomaly. This contrasts with the relative brachiopod and chitinozoan resistances in the course of the Ireviken Event. Also, during the Klonk Event, a moderate faunal turnover, both in benthic and pelagic groups, occurred only near the very beginning of the prolonged ¹³C−enriched timespan across the system boundary, possibly due to progressive dysoxia and temperature drop. The characters point to a peculiarity of the Klonk Event by comparison with the Silurian global events, and some similarity already to the succeeding Devonian transgressive/anoxic episodes.
Źródło:
Acta Palaeontologica Polonica; 2012, 57, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
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 late Silurian-Middle Devonian long-term eustatic cycle as a possible control on the global generic diversity dynamics of bivalves and gastropods
Autorzy:
Ruban, Dmitry A.
Powiązania:
https://bibliotekanauki.pl/articles/94693.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet im. Adama Mickiewicza w Poznaniu
Tematy:
bivalves
gastropods
diversity dynamics
origination
extinction
eustatic changes
Silurian
Devonian
małże
ślimaki
powstawanie
wyginięcie
zmiany eustatyczne
Dewon
Opis:
A long-term eustatic cycle (fall and subsequent rise of the global sea level) embraced the late Silurian-Middle Devonian time interval. Potentially, these sea-level changes could drive global biodiversity. The stratigraphic ranges of 204 bivalve genera and 279 gastropod genera included into the famous Sepkoski database allow reconstructing changes in the total diversity and the number of originations and extinctions of these important groups of marine benthic macro- -invertebrates during this interval. None of the recorded parameters coincided with the long-term global sea-level cycle. It cannot be not excluded, however, that the global sea-level changes did not affect the regions favourable for bivalve and gastropod radiation because of regional tectonic mechanisms; neither can it be excluded that the eustatic control persisted together with many other extrinsic and intrinsic controls. Interestingly, the generic diversity of gastropods increased together with a cooling trend, and vice versa. Additionally, the Ludlow, Eifelian, and Givetian biotic crises affected, probably, both fossil groups under study. There was also a coincidence of the relatively high bivalve generic diversity, initial radiation of gastropods and the entire biota, and the diversification of brachiopods with the Early Devonian global sea-level lowstand, and this may be interpreted as evidence of a certain eustatic control on the marine biodiversity.
Źródło:
Geologos; 2013, 19, 3; 193-200
1426-8981
2080-6574
Pojawia się w:
Geologos
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Siluro-Devonian of Podolia, Ukraine: Paleobiological, biostratigraphic, and geochemical aspects
Autorzy:
Szaniawski, H.
Powiązania:
https://bibliotekanauki.pl/articles/20313.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Silurian
Devonian
Podolia
Ukraine
paleobiology
biostratigraphy
geochemistry
Źródło:
Acta Palaeontologica Polonica; 2012, 57, 4
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
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