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EN
The paper deals with sub-evaporite Badenian deposits (Middle Miocene, Paratethys) that display a sudden appearance of globorotaliid taxa showing preferences in the taxonomic set and coiling direction. An interval of sinistrally coiled Jenkinsella mayeri with proportionally coiled Globoconella bykovae is at the bottom of the studied sequence. It is followed by an interval of proportionally coiled Jenkinsella transsylvanica. Proportionally coiled Globoconella bykovae with a small number of proportionally coiled Jenkinsella transsylvanica are at the top of the Moravian (CPN 7) substage (Orbulina suturalis alias Lagenidae Zone). The sub-evaporite part of the Wielician (CPN 8) substage (Uvigerina costai alias Spiroplectammina Zone) began with a globorotaliid-barren interval (IIC biozone). It is followed by biozone IID displaying three globorotallid peaks amongst globorotallid-barren deposits. Only globoconellas are present in all these three events. Proportionally coiled Globoconella bykovae appeared first. It is followed by proportionally coiled Globoconella minoritesta and sinistrally coiled Globoconella bykovae at the end of the biozone IID. Coiling preferences of globorotaliids have been compared to changes in the hydrographic regime unfolding during the CPN 7 and CPN 8 in the studied area of the Paratethys. The study discovers that the coiling of globorotaliids responded selectively to the hydrographic changes. Globoconella bykovae is highly opportunistic and can tolerate considerable temperature changes. Specimens of this taxon persist to coil proportionally during the sub-evaporite Badenian, except for the shift to sinistral coiling just prior to the Wielician evaporites. Sinistrally coiled Jenkinsella mayeri is the most sensitive to hydrographic changes. This taxon retreated at the onset of the temperature drop during the mid-Moravian cryptic cooling. This cooling is marked by the new jenkinsellid occurrence – proportionally coiled Jenkinsella transsylvanica. Proportionally coiled Globoconella minoritesta is present in the middle of the IID globorotaliid peaks. The globorotaliid coiling data, presented in this paper, has been calibrated to the global stratigraphy. The integrated data (foraminifera, nannofossils, oxygen and carbon stable isotopes, radiometric measurements) supports the view that the CPN 7/CPN 8 boundary is coeval to the Langhian/Serravalian one. In the Polish part of the Carpathian Foredeep, the boundary runs within the Skawina Formation.
EN
The Badenian Salinity Crisis took place at the early/late Badenian boundary and resulted in massive chemical sedimentation in the central Paratethys. The evaporating basin of the northern Carpathian Foredeep left behind gypsum and halite deposits tens of meters thick. As a very good medium for preservation, these evaporites are a fine source of diversified terrestrial palynomorphs. Plant communities reconstructed on the basis of both palynological analysis of sediments from the Bochnia and Wieliczka salt mines, as well as previously published studies from different localities within the evaporite basin, reveal the presence of wetland and mesic environments along the coasts of the northern part of the central Paratethys during the evaporative event. Among the most important taxa are Engelhardia, Ericaceae, Fagus, Liquidambar, Quercus, Taxodium/Glyptostrobus, Tricolporopollenites pseudocingulum, and Ulmus. The most characteristic feature of the palynofloras studied is the large amount (up to even 50%) of Ericaceae pollen in the spectra. Taxa representing a warm-temperate climate predominate in the palynofloras examined; however, representatives of a tropical/subtropical climate (i.a. Mastixiaceae) are also present. The presence of plant communities associated with wetland areas shows that the climate remained humid.
EN
The study is focused on the taxonomic inventory of an intriguing bivalve fauna from the Lower Oligocene Menilite Beds (Dynów Marls) within the Silesian Nappe, Polish Outer Carpathians. Sixteen bivalve species have been identified within the material collected in two small quarries in Jabłonica Polska near Krosno. Stratigraphic and geographic distributions of all recognized species are considered. This assemblage, the first of this kind in Poland and one of three recognized in the Outer Carpathians, shows clear affinities to coeval typical Solenovian faunas from Ukraine to Kazakhstan, with particular comparison made to bivalve faunas from the Menilite Formation (Subchert Member) within the Boryslav-Pokuttya Nappe, Ukrainian Outer Carpathians. Moreover, this study presents an overview of the main aspects and definitions of the date of the Paratethys origin. The main criterion used to define the time of the Paratethys birth is the distinct faunal turnover from the moderately diverse boreal or Tethyan bivalve faunas populating particular basins of the Northern Peri-Tethys in the earliest Oligocene to the uniform, highly endemic fauna inhabiting the newly formed semi-closed basin. This vast inland sea, named Paratethys, was populated by representatives of eight euryhaline bivalve families. They are characterized by extinct Paratethyan genera, such as Bessia Kojumdgieva et Sapungieva, Merklinicardium Popov, Korobkoviella Merklin, Urbnisia Goncharova, Ergenica G. Popov and Janschinella Merklin.
EN
The Badenian section of Anadoly near Kamyanets Podilskyy (Ukrainian Carpathian Foredeep Basin) consists of the Tyras Fm. (gypsum and Ratyn Limestone) and the Ternopil Mb. of the Kosiv Fm. The latter are 5.3 m thick and are composed of dark grey mudstones with limestone intercalations. This study indicates the occurrence of over 54 species of benthic foraminifers and 10 species of planktonics. Benthic foraminifera are represented mainly by calcareous forms; agglutinated tests are very rare. Planktonic foraminifera appear in the upper part of the succession studied. Five benthic foraminiferal assemblages are recognized: A (Elphidium/Lobatula/Astrononion) B (Hauerinidae), C (Cibicidoides/Lobatula), D (Porosononion) and E (Uvigerina/Bulimina). The foraminiferal record indicates deposition in a shallow subtidal environment (20 m depth) of normal marine salinity and temperate waters followed by gradual deepening of the basin to >50 m. Analysis of foraminiferal assemblages indicates that bottom waters were highly oxygenated during deposition of the lower and middle parts of the Anadoly sequence. During deposition of the upper part of the sequence the oxygenation of bottom water gradually decreased, as expressed by a large decrease in the proportion of oxic species and an increase in dysoxic ones. The same set of samples yielded low amounts of palynological organic matter represented by dominant black opaque phytoclasts; bisaccate pollen grains and dinoflagellate cysts are rare. Taxonomically impoverished assemblages of the latter consist of dominant Polysphaeridium and Cleistosphaeridium placacanthum associated with Lingulodinium machaerophorum and a few other taxa. The taxonomically richest assemblage was found in the topmost sample. These changes were interpreted as indicative for increased salinity in the surface water layer, with its maximum in the middle part of the section; the assemblage from the topmost part is characteristic for normal marine salinity.
EN
The Pogórska Wola palaeovalley of combined tectonic and erosional origin dissects the Mesozoic floor of the Carpathian Foredeep Basin to a depth exceeding 1200 m. It formed during Paleogene times presumably due to fluvial and submarine erosion, concentrated along a local pre-Late Badenian graben system. All members of the foredeep’s Badenian-Sarmatian sedimentary fill attain distinctly greater values inside the palaeovalley than on top of elevated plateaux on palaeovalley shoulders. The fill comprises the Early to Late Badenian sub-evaporite Skawina Formation, the laterally equivalent Late Badenian evaporite Krzyżanowice and Wieliczka formations and the supra-evaporite Late Badenian to Early Sarmatian Machów Formation. Over the plateaux and in the highest palaeovalley segment, the evaporites are developed in the sulphate facies Krzyżanowice Formation, whereas in the lower palaeovalley segments chloride-sulphate facies evaporites of the Wieliczka Formation occur. The rock salt-bearing rocks are involved in thrusting and folding at the Carpathian orogenic front, which helps to assess the lateral extent of the Wieliczka Formation in seismic records. The deep palaeotopographic position of the evaporites inside the palaeovalley, combined with their lithological and sedimentary features, point to their formation via subaqueous gravity flow-driven redeposition of originally shallow-water evaporites, preferentially halite-bearing, presumably combined with precipitation from sulphate and chloride brines at the palaeovalley floor. Both the redeposited sediments and the brines must have come from the adjacent plateaux and from a thrust-sheet top basin, approaching from the south on top of the Cretaceous-Paleogene Carpathian flysch thrust wedge.
EN
This study details the petrology and chemistry of the Oligocene succession of the Grybów Nappe in its stratotype-locality in the Grybów tectonic window (Polish Carpathians). The section studied is composed of the Sub-Grybów Beds, the Grybów Marl Formation (GMF), and the Cergowa Beds, representing the middle to upper part of the Oligocene succession. The rocks studied consist of quartz, calcite, Na-plagioclase, muscovite and clay minerals (illite-smectite with 25–30% of smectite and kaolinite). Additionally, hematite occurs in the GMF and chlorite in the Cergowa Beds, respectively. The macerals assemblage of the GMF is dominated by landplant-derived compounds of liptinite, associated with minor amounts of vitrinite representing type II kerogen. The total organic carbon (TOC) content is between 0.45 and 6.16 wt.%. The δ13Corg values of the GMF vary between –27.1 and –27.9‰. The values of both carbon and oxygen isotopic ratios of carbonates range for δ13C from –1.1 to –4.3‰ VPDB, and for O from –1.5 to –4.8‰ VPDB. The concentrations of Co, U, Ni, As, and Mo are higher in the GMF than in the adjacent strata and positively correlate with TOC and S. Values of the TOC/S and V/V+Ni ratios are 0.7 to 3.5 and 0.67 to 0.78, respectively, and indicate anoxic conditions. The ratios of U/Th and V/Cr (0.3–2.2, 1.18–3.18, respectively) suggest the change of oxic conditions to reducing conditions occurred during the GMF deposition. This change could have been preceded by a plankton bloom, initiated by a nutrient-rich freshwater inflow that is inferred from the decrease of the δ13Ccarb values and the terrestrial detritus supply. Thermal alteration of the Grybów Succession is concluded on the basis of smectite illitisation and low δ18O values.
EN
The Upper Badenian marly shales overlying gypsum and the Ratyn Limestone at Shchyrets, Ukraine, contain moderately to well-preserved benthic (calcareous only) and planktonic foraminifers, and palynofacies dominated by bisaccate pollen grains, presumably transported by wind. Both foraminiferal and dinoflagellate cyst assemblages indicate an open marine environment with normal-marine salinity and cool waters. The palaeodepth was ca. 50 m except for the uppermost part of the section studied, where a distinctive deepening is indicated by the dominance of Uvigerina in benthic foraminiferal assemblages and a high P/B ratio. The water was thermally stratified and the differences between the bottom water and the water column show an upwards-increasing trend. Bulimina and Globocassidulina are the most common and dominant component of benthic foraminiferal assemblages, except for the uppermost part where Uvigerina dominates the assemblage. The composition of benthic foraminifer assemblages and δ13C values of foraminifers indicate nutrient-rich waters and mesotrophic to eutrotrophic environments in surface waters, and low oxygenation at the sea floor in the Ukrainian Carpathian Foredeep Basin during the Late Badenian.
EN
Globorotaliids of the Skawina Formation (Badenian) come from deposits representing CPN 7 (Orbulina suturalis Zone) and CPN 8 sub-evaporite Wielician (Globigerina druryi–G. decoraperta Zone alias Uvigerina costai Zone) age. There are two taxonomic groups of globorotaliids in the studied material: globoconellids (Globoconella bykovae and G. minoritesta) and jenkinsellids (Jenkinsella mayeri and J. transsylvanica). There are five stratigraphically-rank intervals of these foraminifers prior to the Middle Badenian salinity crisis in Central Paratethys. The investigated Badenian begins with G. bykovae–J. mayeri association followed by the first occurence (FO) of J. transsylvanica. The closing member of the CPN 7 biozone is the G. bykovae–J. transsylvanica assemblage. The jenkinsellids disappear during CPN 7: J. mayeri first and J. transsylvanica after. Since the base of CPN 8 in situ jenkinsellids have not been noted in the Badenian deposits. The CPN 8 begins with a stratigraphic interval barren of globorotaliids (biozone IIC in the Polish Paratethys). It is followed by episodic appearances of globoconellids (G. bykovae and G. minoritesta) in the sub-evaporite Wielician (IID biozone in Poland). G. minoritesta has been found in only one case so far. The globorotaliid stratigraphic units are distinct and well-correlated with changes in climate and the circulation of water masses in Paratethys. This study provides additional data on Mi3 in Paratethys. It documents a cryptic cooling event in the late Orbulina suturalis Zone (mid CPN 7) located at the late IIA–B assemblage (alias upper lagenide zone) in regional biostratigraphic scale. The event is recorded by J. transsylvanica Acme, matching with circa 1‰VPDB δ18O positive excursion. The event must have resulted in a considerable sea level drop – a trigger of the Moravian ecosystem demolition in the Paratethys environment.
EN
Foraminifers occurring in marls underlying the Middle Miocene Badenian gypsum in the northern Polish Carpathian Foredeep in one borehole section [Młyny (Busko) PIG 1] and in two dewatering pits in operating quarries (Leszcze and Borków) contain well-preserved foraminifers. Sixty-seven species of benthic and twenty-one species of planktonic foraminifers are recorded in the 12-m-thick section of the Młyny borehole. Benthic assemblages are characterized by the dominance of Bulimina and Uvigerina while planktonic assemblages are composed mainly by warm-water orbulinids and Globigerinoides spp. in the lower part of the Młyny section and by temperate-cold water Globigerina spp. in the upper part of the Młyny section as well as the Leszcze and Borków sections. The taxonomic composition of foraminiferal assemblages makes it possible to distinguish two foraminiferal zones in the Młyny borehole: the Orbulina suturalis and Uvigerina costai zones, and only the latter zone is accessible at Leszcze and Borków. The benthic foraminiferal successions in the studied interval suggest oxygenation and productivity changes in the Carpathian Foredeep Basin prior to the Badenian salinity crisis. Four intervals of lowered oxygenation and/or elevated organic flux to the sea-floor are recognized; the intervals in which foraminiferal assemblages suggest marine environments with lowered oxygenation in bottom waters alternate between the intervals where stress markers form less than 50% of the benthic foraminiferal assemblages. Benthic assemblages are moderately to highly diversified, and species have more equal frequencies. The upsection decrease in the proportion of planktonic foraminifers reflects the shallowing of the basin accompanied by a decrease in the temperature gradient between the upper (warmer) and deeper (colder) water beds. The average palaeotemperature of water based on d18O of Uvigerina and Globigerina decreased by ca. 2 and ca. 6°C, respectively (from 9.9 and 17.4°C in the Orbulina suturalis Zone to 7.9 and 11.5°C in the Uvigerina costai Zone, respectively). Below the gypsum, the d18O values of both benthic and planktonic foraminifers show quite large variations possibly due to the salinity increase. Coeval domination of benthic foraminiferal assemblages by Bulimina suggests increased surface water productivity and an increased organic flux to the sea-floor prior to the onset of evaporite deposition and/or salinity increase.
EN
Moundlike, globular to hemispherical bryozoan colonies of Celleporina medoborensis sp. nov. are documented from the calcareous organodetrital, slightly marly facies of the Lower Sarmatian (Volhynian) serpulid-microbialite reefs, in the Polupanivka and Ditkivtsi quarries (Medobory Hills), located at the northeastern margin of the Carpathian Foreland Basin (Central Paratethys) in western Ukraine. The colonies of C. medoborensis are multilamellar, often with a subcircular hole and occur together with numerous cyclostome bryozoans (crisiids, tubuliporinids, branching colonies of entalophoroids) as well as schizoporellid and cryptosulid cheilostomes, accompanied by a few macro- and micro-fossil taxa. The combination of morphological characters such as: thick radial ribs in the pseudoporous, variably-shaped area of the ovicell, and one or two small adventitious oral, as well as large vicarious avicularia are the main characteristic features of species. The rich occurrence of the celleporiform colonies of C. medoborensis sp. nov. within the fine-grained calcareous sands of Polupanivka and Ditkivtsi suggests a shallow-water setting and high availability of soft substrates, probably dominated by calcareous algae upon which the bryozoans may have settled in the Medobory reef biota during the Early Sarmatian.
EN
The Neogene and Quaternary depositional and structural characteristics of the southwestern Croatian Pannonian Basin System (CPBS) are unique within the Pannonian Basin System. Due to its position at the basin margin, the area was covered by shallow and partially isolated parts of the Pannonian Sea in the Badenian (Middle Miocene). Later, in the Pannonian and Pontian ages, the area contained several brackish lakes, the largest being Sava Lake and Drava Lake. Tectonic events, sedimentation and depositional mechanisms occurring during the Neogene in the CPBS have revealed that those areas can be considered as former shallow seas or lakes dominated by clastic sedimentation. Marine coarse-grained clastic sedimentation took place during the Badenian, with local sources of material and numerous alluvial fans developed during the first transtensional phase. In the Pannonian and Pontian (Late Miocene), sediments were deposited by turbidity currents from a single, distal material source located in the Eastern Alps during the second transtensional tectonic phase.
EN
Foraminifera from newly exposed outcrop sections located in a Middle Miocene piggyback basin of the Outer Carpathians Nowy Sącz Basin indicate an environment of normal saline waters on the inner shelf and a temperature not lower than 18oC. The area was ideal for the proliferation of: Miliolina spp., Elphidium crispum, Ammonia beccarii and Pararotalia. The habitat below the sediment surface was not colonised by foraminifera. Planktonic foraminifera are absent. The age of the population studied is referred based on the climate-related data, to the Orbulina suturalis Zone of the Miocene Climate Optimum.
EN
Middle Miocene foraminifera from the Skawina Formation of the Upper Silesia Basin have been analysed. The stable oxygen and carbon isotope signatures in Globigerinoides quadrilobatus (shallow pelagic), Globigerina bulloides (deeperpelagic) and Uvigerina spp. (benthic) tests show a temporal pattern of changes in the sections studied. The foraminiferal assemblage biozones of the Badenian that were identified earlier, on the basis of taxonomic composition, correspond to changes in the foraminiferal ẟI8O and ẟI3C values. The CPN7/CPN8 transition - as the Moravian/Wielician border - is marked by distinct isotopic events: a ẟ18O increase (IIAB/IIC boundary) followed by a ẟ13C decrease (IIC/IID boundary).
EN
Taxonomic, quantitative and isotopic study of foraminifera from mudstone and claystone xenoliths incorporated into slump facies of the Stratified Salt Member of the Wieliczka deposit shows that the majority of xenoliths represent the CPN 8 biozone (Wielician substage, Badenian, Middle Miocene). The share of the CPN 7 biozone is minor; it was recorded in two of 26 samples analysed. The source area of xenoliths was the basinal part of the Carpathian Foredeep, located far off the shoreline (shallow-water taxa are not present in the samples); it represents the upper bathyal zone, in oxygenated conditions. Inbenthic, eutrophic and opportunistic foraminifers dominate the benthic environment of the CPN 8 span of time. Increased d18O values of the Globigerina bulloides tests (from +1.7‰ in CPN 7 to +2.3‰ in CPN 8 sediments) was due to the change from the Middle Miocene Climate Optimum to the Middle Miocene Climate Transition at the CPN 7/CPN 8 boundary. This palaeoclimate event is the marker of the Moravian/Wielician chronostratigraphic boundary in the Central Paratethys. The Wielician shows the distinct taxonomic reduction of the Moravian planktonic foraminifera and includes the Globigerina bulloides Acme.
EN
This is the first Paratethyan record of a minute scallop species Parvamussium fenestratum (Forbes, 1844). The species was found in Middle Miocene (Upper Badenian) clayey deposits in the Surzha borehole, the Ukrainian Carpathian Foredeep Basin. Examination of other Parvamussium specimens stored in the Museum of the Earth in Warsaw and in the Hungarian Natural History Museum in Budapest revealed further Paratethyan records of Parvamussium fenestratum. These specimens, previously referred to Parvamussium felsineum (Foresti, 1893), were identified in the Middle Miocene faunas of Poland (Monastyrz and Długi Goraj, Roztocze Hills) and Hungary (Makkoshotyka, Tokaj Mts.). In the Mediterranean Neogene this extremely rare species has been reported from the Lower Miocene (uppermost Burdigalian) of Italy and from the Lower Pliocene (Zanclean) of Spain. Research on the Oligocene-Miocene succession in the Paratethys has shown representatives of Parvamussium Sacco, 1897 to be moderately abundant in clayey facies in different basins and the genus is regarded as biostratigraphically important. Data on the distribution of other Paratethyan and Neogene Mediterranean Parvamussium species viz., Parvamussium bronni (Mayer, 1861), P. duodecimlamellatum (Bronn, 1831), P. felsineum (Foresti, 1893) and P. miopliocenicum (Ruggieri, 1949) are reported. Finally, palaeobiological and palaeobiogeographical characteristics on the genus Parvamussium Sacco, 1897 the Early Cretaceous to Recent time span are described.
EN
Specimens of Middle Miocene (Early Badenian) Amphistegina from the Polish Carpathians were examined. A section, sampled at the Olimpów quarry, displays chloralgal carbonates, rich in rhodolith nodules. Symbiont-bearing foraminifera (Amphistegina, Elphidium and Asterigerinata) constitute 15–57% of the total foraminifera assemblage. Amphistegina hauerina d’Orbigny, 1846 is the only species of the genus in the deposits studied. The sensitivity of larger foraminifera to water turbulence and light availability was applied in a reconstruction of the community habitat. The diameter and thickness of the Amphistegina tests indicate that the habitat was a zone of low light penetration and weak energy – a palaeoenvironment, similar to that of the modern A. radiata (Hottinger et al., 1993). Changes in the sphericity of the Amphistegina tests reflect a temporal drop of bathymetry in the middle part of the section. This is supported by other environmentally controlled features of the foraminiferal assemblage: the percentages of both planktonic and symbiont-bearing forms, as well as the proportions of robust and flat forms of Elphidium. It is possible that this variation in depth was due to eustatic changes in sea level, caused by Event Mi3 of the Middle Miocene climatic cooling. The spiral diameter of the test was at its lowest value then, indicating that maturity was reached at a faster rate. The period of shoaling offered the best life conditions for Amphistegina in this particular area.
EN
The huge lithosome of the Middle Miocene (Early Badenian) Mykolaiv Sands, developed at the external margin of the Fore-Carpathian Basin in western Ukraine, is recognized to represent a shallowing-up sequence. Special attention is paid to burrows of the Ghost Crab Ocypode which are pantropical in present-day littoral habitats. In the Stratyn section, burrows of this type become a crucial tool in the interpretation of basin bathymetry, which starts from distal offshore depths, through the foreshore, to the backshore where the Ocypode burrows record a temporary break in sedimentation. Lithification of the sand layers and the Ocypode burrows subsequently progressed in beachrock mode. The Stratyn section demonstrates that the development of submerged shoals and/or emergent parts, throughout the huge mass of the Mykolaiv Sands, is probably responsible for their great variation in thickness in western Ukraine, which has long proved difficult to explain.
PL
W strukturach wzrostowych halitu typu szewron w basenie zakarpackim (Ukraina) stwierdzono występowanie pierwotnych inkluzji, które mogą być pomocne przy określeniu składu chemicznego solanek badeńskiego basenu ewaporatowego. Ciekłe inkluzje występujące w sedymentacyjnym halicie badane były metodą analizy ultramikrochemicznej. Koncentracja solanek zakarpackiego basenu była wysoka - zbliżona do średniego etapu sedymentacji halitu. Zawartość jonów: K+ zawierała się w przedziale 10.6-17.6 g/l, Mg2+ w zakresie 31.4-58.3 g/l, a SO4 2- w przedziale 22.4-39.0 g/l. Na podstawie badań składu chemicznego głównych jonów stwierdzono, że solanki basenu zakarpackiego były nasycone względem halitu i podobne do solanek z innych badeńskich basenów.
EN
The primary fluid inclusions, which may be helpful in detemining the chemical composition of brines in the Badenian evaporite basin, were found in the chevron halite crystals from the Transcarpathian Basin (Ukraine). Fluid inclusions in sedimentary halite were examined with the use of ultra-microchemical analysis. Concentration of brines was high - close to the middle stage of halite sedimentation. The content of ions: K+ ranged from 10.6 g/l to 17.6 g/l, Mg2+ from 31.4 g/l to 58.3 g/l, and SO4 2- from 22.4 g/l to 39.0 g/l. Based on the chemical composition of major ions it was concluded that the brine from the Transcarpathian basin was saturated (to the stage of halite crystallization) and was similar to the Badenian brines from other basins.
EN
Qualitative and quantitative characteristics of the palynological content of the Upper Badenian strata at Kudryntsi (western Ukraine) indicate that this succession was deposited in variable environments. The basal siliciclastic series shows a very low content of palynological organic matter and palynofacies, which indicate a restricted environment and/or unfavourable conditions for the palynomorph preservation. The presence of dinoflagellate cysts (and composition of their assemblages) in the upper part of organodetrital limestones and the overlying rhodoid limestones indicates a typical shelf environment. Taxonomically variable dinoflagellate cyst assemblages from particular samples reflect gradual environmental changes – from environments of slightly increased salinity of seawater (strata overlying the siliciclastic series) to open marine, more remote environments during deposition of the upper part of the section examined. The gradual deepening of the sea and decrease of salinity is supported also by the succession of foraminiferal assemblages, which undergo gradual changes from Elphidium spp. assemblages, through Miliolidae assemblage, Lobatula lobatula assemblage, Neoconorbina spp. assemblage to Cibicidoides assemblage. The Late Badenian foraminiferal assemblage from Kudryntsi contains two species common for the Sarmatian, i.e. Elphidium reginum and Elphidium koberi, the latter species known so far from the Sarmatian.
EN
The Late Badenian coralline algae-vermetid reefs and the Early Sarmatian serpulid-microbialite reefs distributed widely in the northeastern and eastern borders of the Carpathian Foredeep Basin contain an excellent bivalve record and show how the bivalve faunas reflected the temporary closure of seaways between the Paratethys and the Mediterranean around 13.3 Ma. within the Late Badenian reefs, 116 bivalve species and three bivalve associations are recognized. After a dramatic change of environmental factors, the Early Sarmatian reefs hosted 12 bivalve species, grouped in four associations. These are thought to have been controlled largely by salinity and to represent decreased and/or fluctuating salinity regimes. An integrated approach, using benthic fauna, sedimentological and isotope data, enabled interpretation of the origin of the serpulid-microbialite reefs. The changes in the palaeogeography of the Paratethys and sea-level oscillations around the Badenian/Sarmatian boundary played an important role in the distribution, extinction and radiation of the bivalves. The definitive closure of the extensive seaway connecting the Paratethys with the Mediterranean caused not only severe extinction of the bivalves inhabiting the sandy facies during the Late Badenian but also the sudden evolution and dispersal of a few opportunistic species that were ancestral forms to Sarmatian taxa. The composition of the bivalve assemblages and the ecological requirements of particular species prove the mixo-mesohaline character of the Sarmatian Sea (30-18[per-mille]) and indicate an eastward decrease in salinity.
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