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EN
The paper concentrates on seasonal and spatial variations of sub-daily water temperature dynamics in lowland agricultural streams. Temperature monitoring was carried out in 24 sampling sites distributed along the tributaries of the Wkra River during the hydrological year 2021. Statistical analysis of the obtained data documented the highest water temperature dynamics in the morning, from 5:00 to 9:00 CEST, while the lowest - from 14:00 to 18:00 CEST. Seasonally, greater water dynamics were noted in the winter, expressed by a coefficient of variation reaching up to 100%. Spatially, the highest dynamics occurred in sites with the lowest proportion of riparian vegetation, while the lowest dynamics was related to higher catchment area. In the winter, the minimum daily values were recorded most frequently in the morning hours, while maximum values in the afternoon. A similar pattern was observed in the summer, but with much lower dispersion of the relative frequencies. It was found that in the winter, the dominant influence on temperature dynamics was exerted in the upstream catchment area, while in the summer, a negative relationship with riparian shade was marked. The findings suggest that the presence of riparian vegetation reduces diurnal dynamics of water temperature and is simultaneously extremely important in prolonging the duration of optimum fluctuation, responsible for the proper development of poikilothermic organisms.
EN
A new site of Eemian organogenic deposits in S3up (central Poland) has revealed an intermittent record of several phases within this interglacial. Pollen based studies of the core S3-19, drilled at the littoral zone of the palaeolake, indicated the absence of the E2, E3, E6 and an incomplete record of the E4 and E5 zones of the typical pollen succession. Results of other proxies (plant macrofossils, Cladocera, molluscs, NPPs, isotopes) supported the conclusions derived from the pollen diagram regarding the high humidity and lake water level during the E4 (Corylus-Quercus-Tilia) phase and at the beginning of the E5 (Carpinus-Corylus-Alnus) phase, when the fossil lake was most extensive. Thus, the lack of a record of the E3 and E4 RPAZs was associated with water level lowering and a less humid climate. The results stand in agreement with several other Eemian records from central Poland.
EN
Geochemical and plant macrofossil analyses of the Żabieniec mire deposits and the palaeoenvironmental changes they record of the past several thousand years constitute an important source for palaeogeographical reconstruction of the Polish Lowland. We describe the phases of the basin’s development from the final part of the Plenivistulian (MIS2), through the Late Glacial and the entire Holocene, encompassing changes determined by both regional and global factors in the surrounding environment, and habitat transformations in the limnogenic mire. The kettle-hole infill of the Żabieniec mire is the only documented example in Central Poland of a succession of biogenic deposits exceeding 10 m in thickness in such a setting. Deposition initially took place in a lake environment, which led to a shallowing of the lake that persisted until the end of the Mesoholocene.
EN
The paper is focused on the palaeographic development of the western part of the Holy Cross Mountains, Poland, during the maximum extent of the Sanian 2 (MIS 12) ice sheet and its retreat. The studies were based on archival cartographic data, coupled with new lithological and petrographic analyses of limni- and fluvioglacial sands, i.e., grain-size composition, quartz grain morphology and heavy mineral analysis, as well as analysis of the erratic material of tills. The results confirm the regional variability of the erratic material in the Sanian 2 tills and point to the long-term development of fluvioglacial sands cover documenting cold climate conditions. They also evidence that the western part of the Holy Cross Mountains was the area where two oppositely directed ice sheet lobes (Radoszyce and Sandomierz) advanced during the Sanian 2 Glaciation and that deglaciation of the area took place in two stages. Huge quantities of meltwater released at that time contributed to the intensification of earlier initiated karst phenomena, as well as filling of the existing caves by fluvioglacial sands.
PL
Strefa środkowa złóż żwirów i piasków obejmuje środkową i południową część Niżu Polskiego, do której zaliczono 6 województw. Spośród trzech stref jest największa powierzchniowo (44,3% powierzchni kraju) i ludnościowo (43,7% ludności), jednak udokumentowane zasoby żwirów i piasków w tej strefie są najmniejsze i wynoszą 26,7% krajowych zasobów bilansowych i 27,5% zasobów przemysłowych. Udział wydobycia tej strefy w wydobyciu krajowym w 2018 r. wyniósł 28,4%.
EN
Petrographic analysis, including the indicator erratics count method of coarse pebbles (20–60 mm), was performed for the first subsurface layer of the glacial till in the vicinity of the city of Radom. Crystalline rocks comprise 60% of the sample, whereas carbonate and clastic sedimentary rocks total 18% and 15%, respectively. Among the crystalline rocks, 14% clasts were identified as indicator erratics. The majority of the indictor erratics originated from the Åland region (63%). Significant contributions were also derived from the central Baltic Basin (12%), Ångermanland (9%) and Uppland (9%) regions. Trace amounts are recorded from the northern Baltic, Dalarna and Småland regions. The spatial distribution of crystalline erratic source areas suggests material incorporation into an ice sheet mainly from central-eastern Fennoscandia. The indicator assemblage composition indicates the Odranian (MIS 6) origin of the till. The majority of the erratic sedimentary rocks were derived from the central and southern Baltic Basin while local rocks comprise a minor proportion. The relatively low carbonate clasts content indicates that the till was affected by partial decalcification resulting from post-depositional chemical weathering. This study supplements the results on erratic pebble provenance in the glacial tills of Middle Polish Glaciation Complex in Poland.
EN
The article is an attempt to find relations between geology and the dynamics of the Mesozoic surface of the Łódź Synclinorium, the Radomsko Elevation and the Bełchatów Graben and the present relief on the border of the Polish Lowlands and Uplands in its central part. Fossil relief has been compared with the present one as related to the extent of the recession phases of the Saalian (Wartanian) ice-sheet. A significant convergence has been found between the Mesozoic surface plain and the main morphologic elements. The role of elevations and fossil valleys has been stressed as stable forms in the pre-Pleistocene and contemporary landscape. Also stressed has been the meaning of grabens and elevations enforcing longer stoppages of the Wartanian stadial of the Middle Polish Glaciations.
EN
The tectonic settings investigated by several seismic projects in previous research targeting the structure in Central Poland mainly focused on the Earth’s crust. In this paper, we present P-wave velocity verification in the uppermost mantle beneath LUMP profile towards SSE-NNW. Using recordings of 36 DATA-CUBE recorders from ca. 300–490 km far earthquake in coal mine “Janina” in southern Poland, we calculated travel times to verify P-wave velocity below the Moho boundary from previous studies. It shows that a significantly lower mean velocity value should be used for the upper mantle while counting these offsets of travel times in the SSE-NNW direction than that used on previous profiles. We present two possible models: first, the most simple one that fits the observed first arrivals, and the second with a low-velocity layer beneath the Moho boundary. In both cases, we used a priori crustal model focusing only on P-wave velocity in the uppermost mantle. Both of them significantly improved adjustment of travel times to the observed data. To evaluate the tendency of adopting too high velocities beneath the Moho, we used also 11 broadband stations, Reftek 151-121 “Observer”, from “13 BB Star” passive experiment and 6 STS-2 seismometers from permanent stations of the Polish Seismological Network (PLSN).
EN
The possible occurrence of the Oldest Halite (Na1) unit of the Zechstein PZ1 cyclothem in the Kłodawa salt dome was a discussed matter for many years. Profiling and sampling of the evaporite Zechstein succession (a transition of PZ1 to PZ2 cyclothems) visible in a corridor of the "Kłodawa” Salt Mine at the mining level -650 m, located near the NE marginal pillar of the dome, were done in 2011. The studied section includes rock salt, shale, sulphate and carbonate rocks inclined at 60-90o to the NE and represents a normal succession of the PZ1 and PZ2 cyclothems. The normal succession of the top part of the PZ1 cyclothem consists of two lithological units: 1) rock salt complex (extending over a distance of ca. 5.8 m), defined as the Oldest Halite (Na1) lithostratigraphic unit, and 2) anhydrite bed, c.a. 1.3 m thick, distinguished as the Upper Anhydrite (A1g). These deposits are overlain by 4 lithological units, considered as those creating the normal sequence of the lower part of the younger PZ2 cyclothem. The first one is a dolomitic shale bed, ca. 3.7 m thick, defined as the Stink Shale (T2). It is overlain by a dolomite layer, 0.3-0.5 m thick, representing the Main Dolomite (Ca2), and by an anhydrite series, over 17 m thick, attributed to the Basal Anhydrite (A2). The studied section ends with a rock salt complex, ca. 4 m thick, interpreted as the Older Halite (Na2). The bromine (Br) content in both salt units is relatively low: 81-86 ppm (7 samples) in the Na1 unit and 54-77 ppm (4 samples) in the Na2 unit, with a distinct upward-increasing trend in the latter. Similar low Br values and their distribution trends were characteristic for the top of the Na1 standard bromine curve in Poland and for the lower part of such curve for the Na2 salts. This geochemical similarity could support a proper stratigraphic position of both units. The analysed section was interpreted as a tectonic slice or intrusion, composed of Na1 rock salt overlain with the younger A1g sulphate, incorporated within the folded complex of Na2 rock salt. Such image confirms the current opinion of a more complicated internal structure of the so-called "marginal anticlines” within the Kłodawa dome, composed of intensively folded both salt units. It also documents that the oldest Zechstein evaporites (chlorides and sulphates) could occur above within the dome section than was stated earlier.
EN
An economical and easy-to-implement technique is outlined by which the mean nocturnal atmospheric mixing state (“stability”) can be assessed over a broad (city-scale) heterogeneous region solely based on near- -surface (2 m above ground level [a.g.l.]) observations of the passive tracer radon-222. The results presented here are mainly based on summer data of hourly meteorological and radon observations near Łodź, Central Poland, from 4 years (2008–2011). Behaviour of the near-surface wind speed and vertical temperature gradient (the primary controls of the nocturnal atmospheric mixing state), as well as the urban heat island intensity, are investigated within each of the four radon-based nocturnal stability categories derived for this study (least stable, weakly stable, moderately stable, and stable). On average, the most (least) stable nights were characterized by vertical temperature gradient of 1.1 (0.5)⁰C·m-1, wind speed of ~0.4 (~1.0) m·s-1, and urban heat island intensity of 4.5 (0.5)⁰C. For sites more than 20 km inland from the coast, where soils are not completely saturated or frozen, radon-based nocturnal stability classification can significantly enhance and simplify a range of environmental research applications (e.g. urban climate studies, urban pollution studies, regulatory dispersion modelling, and evaluating the performance of regional climate and pollution models).
EN
The paper examines spatial and seasonal variations in diurnal water temperature dynamics in lowland rivers. Temperature data was obtained from digital temperature loggers located in nine sites across the Mazovian Lowland during the hydrological year 2016. On the basis of measurement data, mean, maximum, and minimum daily ranges were calculated in the monthly timescale, as well as the timing of extreme temperatures during the day. The results indicate that water temperature dynamics of lowland rivers have a clear seasonal pattern, with the highest variations of temperature in May and June and the lowest in January. Statistically significant differences were found in the daily temperature range between groups of the investigated sites; a higher diurnal temperature range was observed in sites draining a smaller catchment area, while larger rivers were generally more thermally stable in the daily timescale. There was also found an effect of anthropopressure on diurnal temperature dynamics in urbanized catchments, mainly due to impoundments and sewage inflows. Maximum water temperature in the studied sites usually occurred in the morning, from 06:00 to 10:00 CEST, while minimum temperature occurred in the late afternoon, from 14:00 to 18:00 CEST. Spatially, the timing of the maximum and minimum water temperatures during the day was similar in all of the investigated sites, with no statistically significant differences. However, cluster analysis indicated that in the summer half of the year the timing of the extreme temperatures was more varied between investigated sites. The results provide new insight into short-term river thermal behaviour and they are valuable in the context of game fisheries due to the significance of daily temperature variations in fish activity and feeding.
PL
Celem pracy było określenie przestrzennego i sezonowego zróżnicowania dobowej dynamiki temperatury wody w niewielkich rzekach nizinnych. Dane pomiarowe uzyskano za pomocą cyfrowych rejestratorów temperatury wody, które zlokalizowano w dziewięciu profilach rzek Mazowsza w roku hydrologicznym 2016. Na podstawie danych pomiarowych obliczono średni, maksymalny i minimalny dobowy zakres temperatury w ujęciu miesięcznym, a także względną częstość występowania ekstremalnych wartości temperatury w poszczególnych godzinach. Wyniki wskazują, że dobowa dynamika temperatury wody odznaczała się wyraźną sezonową zmiennością; największe dobowe wahania temperatury wody były obserwowane w maju i czerwcu, natomiast najmniejsze w styczniu. Wykazano ponadto istotne statystycznie różnice zakresu dobowego temperatury wody między analizowanymi profilami; większy zakres dobowy był charakterystyczny dla profili pomiarowych zamykających zlewnie o mniejszej powierzchni, natomiast większe rzeki były na ogół bardziej stabilne termicznie. Stwierdzono również wyraźny wpływ antropopresji na dobową dynamikę temperatury wody, przede wszystkim w postaci zrzutów wody ze stawów oraz zbiorników, jak również ścieków z oczyszczalni. Temperatura minimalna występowała w przypadku badanych rzek najczęściej rano – od 06:00 do 10:00 CEST, natomiast temperatura maksymalna późnym popołudniem – od 14:00 do 18:00 CEST. Okres występowania ekstremalnych wartości temperatury wody w ciągu dnia był zbliżony; metoda aglomeracji wykazała jednak, że w półroczu letnim zaobserwowano większe zróżnicowanie czasu występowania wartości ekstremalnych, szczególnie temperatury maksymalnej. Wyniki badań wzbogacają wiedzę dotyczącą warunków termicznych wód płynących, wydają się również interesujące w kontekście wędkarstwa sportowego oraz rybactwa.
PL
Praca przedstawia obserwacje gatunków roślin naczyniowych znalezionych głównie w latach 2015–2017, na wybranych stanowiskach Polski Środkowej, w okolicy Radomska, Sulejowa oraz Piotrkowa Trybunalskiego. Ogółem stwierdzono 58 gatunków roślin naczyniowych. Spotykano gatunki torfowisk przejściowych i wysolich tworzące specyficzną mozaikę Liparis loeselii, częściej Epipactis palustris oraz gatunku z rodziny Parnassia palustris na podłożu wapiennym. Gatunkiem o przypuszczalnym statusie efemeryta jest stwierdzony w okolicach Piotrkowa Trybunalskiego Fallopia aubertii. Zauważono zjawisko wędrówek kilku gatunków, np. w przypadku rodzaju Bidens czy rodzaju Lepidium. Znaleziono także gatunki klasy Oxycocco-Sphagnetetea, szczególnie narażone na zanik z powodu eutrofizacji, a także z klasy Scheuchzerio-Caricetea nigrae. Prawidłowym rozwojem charakteryzowała się Scheuchzeria palustris. Z przeprowadzonych analiz chemicznych próbek z wierzchniej warstwy torfowych uwagę skupia zróżnicowanie takich cech glebowych jak C:N, pH oraz metali ciężkich. Pomimo bliskości ośrodków przemysłowych nie stwierdzono przekroczenia stężeń metali ciężkich. Przeprowadzona analiza statystyczna nie wykazała istotności parametrów w przedziałach wartości oraz korelacji między otrzymanymi wynikami. Reasumując, torfowisko z udziałem Scheuchzeria palustris znajduje się w trakcie przemian, co dokumentuje różnorodność występującej flory. Roślina gatunku Scheuchzeria palustris współwystępuje z gatunkiem Carex limosa, wydając sporo nasion i rozmnażając się wegetatywnie.
EN
There were 58 species in the analyzed area, some of them occurred in three locations. A few of the issues discussed indicate the explanation of several phenomena occurring amongst both rare plants which are sometimes legally protected. Some of them are included on the red list the exemple rare plants Scheuchzeria palustris regarded as an relict boreal and orchids species. There have recordet degration species included those preffering alkaline substrates and Oxycocco-Sphagnetes classe. The study of Scheuchzeria palustris was conducted on one recent stands in the Łódz region, in the Czarny Ług Reserve near Wolbórz. There is an emphasis on the migration of plants which in some cases are previously cultivated by man. Juncus bulbosus in two forms, was found in ecotonal zones with wariable water condition. There nereumougs alien species. An important issue is the issue of anthropogenic impact. on which it usually grows. The statistical analysis carried out using a descriptive method for the listed species, in most cases showed a variation of heavy metal, starting from weak ones such as Pb (non tand stronger ones such as Cr. Apart from heavy metals, high in case of Ca0 content and low with reference to Ph and C:N). characteristic in evolution the soils for themporary and oligotrophe boogs.
EN
The Early Kimmeridgian of the Wieluń Upland and adjoining regions, after the decline of sedimentation of the deep-neritic sponge megafacies (Częstochowa Sponge Limestone Fm.) and associated limestones and marls with poor benthic fauna (Pilica Fm.) during the Planula Chron, showed the subsequent development of moderately shallow-water biostromal chalky limestones with siliceous sponges and corals, replaced laterally by micritic limestones and marls (Prusicko Fm.) during the Platynota Chron and the earliest Hypse¬locyclum Chron. Towards the north and south shallow-marine carbonate platforms occurred (represented by deposits of the “oolitic” fm.), whereas towards the north-west and west deeper marine facies, represented initially by limestones with siliceous sponges (Częstochowa Sponge Limestone Fm.), and later during the Hypselocyclum Chron by bedded limestones and marls with ammonites (Burzenin Fm.) were deposited. This palaeogeographic pattern was controlled by the synsedimentary tectonics. The detailed biostratigraphical classification of the deposits studied from the Platynota to the Divisum zones, and their lithological character, enable the recognition of the primary sedimentary cyclicity by comparison with the well dated short eccentricity cycles in the coeval succession of south-eastern France. The two appendixes enclosed give the characteristics of: (1) the characteristics of the ammonite faunas especially of the families Ataxiocerati¬dae and Aulacostephanidae (where two new species are established – Balticeras samsonowiczi sp. nov., and Rasenioides glazeki sp. nov.); (2) the newly established lithostratigraphical units: the Prusicko Fm., and the Burzenin Fm., and the smaller rank units (members, beds) recognized therein.
EN
The paper presents results of a study of crevasse splay deposits from the Miocene of central Poland near Konin. These mineral deposits occur within the 1st Middle-Polish lignite seam of Middle Miocene age, which is exploited from the Tomislawice lignite opencast mine. They consist of fine-grained sands with an admixture of plant detritus at the top and bottom layers, where the muddy-sandy clasts are present. The investigated crevasse splay deposits are predominantly massive or horizontally stratified, and they occasionally reveal small- to large-scale (planar, trough and ripple) cross-stratification. Thus, they are interpreted as representing dense gravity flows, sheet flows, and channelized flows of variable energy. The crevasse splay was formed subaerially during sudden flood conditions on the floodplain covered by a low-lying mire with predominant herbaceous vegetation. The description of the crevasse splay deposits from the Miocene of central Poland can be helpful in better understanding the sedimentation conditions of relatively thick lignite seams.
EN
Zones of Cl anomalies in Mesozoic and Cenozoic aquifers, defined as groups of wells with concentration of the chloride ion in groundwater exceeding 60 mg/dm3, were mapped on the basis of 12 000 archival chemical analyses. These zones are predominantly developed in tectonic conditions enabling the inflow of Mesozoic salt waters into useful aquifers: 1) fault zones, 2) hydrogeological windows above salt anticlines and elevated tectonic blocks, and 3) salt diapirs. As a result, significant decline in groundwater quality has been reported from many intakes due to the elevated concentration of chlorides, sodium and the amonium ion.
PL
Wśród form geomorfologicznych Kotliny Szczercowskiej znaczną powierzchnię stanowią równiny torfowe. W artykule przedstawione są trzy przykłady torfowisk, dwa z nich powstały w paleomeandrach Widawki, położonych w obrębie dna dolinnego, trzecie leży w obniżeniu na terasie nadzalewowej, otoczonym piaskami eolicznymi. Rozpoznana została miąższość utworów biogenicznych, a w wybranych profilach wykonano oznaczenia parametrów fizykochemicznych i wydatowano spągowe warstwy torfów. Akumulacja torfów rozpoczęła się w późnym vistulianie i trwała w holocenie. W torfowiskach położonych w dnie doliny odłożyły się głównie torfy niskie, zaś w torfowisku położonym w otoczeniu form eolicznych torfy przejściowe i wysoki. Położenie geomorfologiczne znajduje również odbicie we współczesnym stanie torfowisk, które leżą w brzeżnej części leja depresji powstałego w otoczeniu odkrywki węgla brunatnego.
EN
In Szczerców Basin peatlands have a significant participation among geomorphological forms. The article presents three examples of peatlands, two of them are formed in palaeochannel of Wiawka river, in valley floor, third one is located in small depression in high terrace, surrounded by aeolian sands. Thickness of biogenic deposits were examined and in selected cores were measured basic physico-chemical parameters. The bottom of peat layers was dated of radiocarbon method. Accumulation of peat series was started in Late Vistulian and gone in Holocene. In peatlands located in valley floor peat was deposited in fens, in high terrace it was transitional and raised peatland. Geomorphological features are important for the modern situation of peatlands, because they lie in the marginal part of the depression of ground water table, caused by the opencast mine of brown coal.
EN
Spring-fed fens in Wardzyń represent the rare group of alkaline mires supplied by artesian groundwater. Using multidisciplinary methods (including sedimentological, hydrometric and hydrochemical, pollen, macrofossil, malacological, geochemical, radiocarbon dating, and stable oxygen and carbon isotope analyses) we have been able to (1) reconstruct the main phases of spring-fed fen development, and to (2) determine the cause of Neoholocene groundwater ascension responsible for the mire inception. These phases are characterized by cyclic organic (peat) and carbonate (tufa) sedimentation associated with the Holocene fluctuations in humidity and temperature. The beginning of the activation of hydrological systems (involving the flow of confined groundwater of the Cretaceous aquifer) at Wardzyń occurred in the Subboreal period of the Holocene, after a long episode of decreased humidity initiated ca. 4.2 ka cal BP.
18
Content available remote Climate-driven changes to streamflow patterns in a groundwater-dominated catchment
EN
This study aims to investigate trends and regime changes in streamflow and basic factors driving these changes. The investigated area is located in central Poland and is influenced by temperate transitional climate. New insight is provided into the phenomenon of past climatedriven changes to streamflow patterns over a 65-year period (1951– 2015). The Mann–Kendall test for monotonic trends and the CUSUM test are used to determine the presence or absence of changes in climatic variables, shallow groundwater level, and streamflow. Time series are explored to detect the direction of trends and the period when the significant change occurred. Differences in climatic conditions and streamflow patterns are discussed for two sub-periods, before and after the change. Overall, the results suggest stability in precipitation, with limited evidence for change in the annual amount, but reveal a significant change in streamflow regime in the 1980s, attributed to higher temperature driving evapotranspiration and reducing shallow groundwater recharge. It is concluded that the catchment is prone to increased evapotranspiration and in effect to greatly reduced runoff.
EN
Tithonian (= “Middle Volgian”) carbonate rocks are exposed in Owadów-Brzezinki quarry 19 km southeast of Tomaszów Ma-zowiecki, central Poland. In the upper part of the Sławno Limestone Member, chitinoidellids have been identified in thin sections from three samples, only. Therefore, the documented part of the Chitinoidella Zone in Owadów-Brzezinki quarry is about 0.3 m thick. The identified chitinoidellid taxa suggest that this assemblage represents the Upper Tithonian Boneti Subzone. The Chitinoidella Zone occurs at the top of Unit I and correlates with the uppermost interval of the Zarajskensis Horizon (Matyja, Wierzbowski, 2016). Other microfossils identified in the Chitinoidella Zone consist of Saccocoma sp. and benthic foraminifera of the genus Planularia. Calcareous dinoflagellate cysts (Cadosina semiradiata semiradiata Wanner and C. cf. semiradiata semiradiata Wanner) occur above the chitinoidellid assemblage, in the strata corresponding to the Gerassimovi Subzone of the Virgatus Zone (Matyja, Wierzbowski, 2016). Calcareous nannofossils are extremely rare in the thin sections studied; only one small specimen was seen, identified as Rhombolithion minutum (Rood et al., 1971) Young et Bown 2014. In contrast, microbial filaments are frequently observed in the studied thin sections. Their shape and pattern are reminiscent of some recent Cyanobacteria of the order Nostocales, however the Tithonian microbial filaments are much thinner.
EN
Radiolarian assemblages from the uppermost Oxfordian (Hypselum Zone) deposits of two sections (Katarowa Góra and Bobrowniki) in the Wieluń Upland (central Poland) are studied for the first time. The overall composition of the assemblages is characterized by low taxonomic diversity, with many individuals of spherical morphotypes, with dominance of the family Williriedellidae and Gongylothoracidae, among the nassellarians. The radiolarians show features mostly of the Northern Tethyan fauna. Additionally, more cosmopolitan forms consisting of spumellarians and of cold water representatives of the family Parvicingulidae appear in the middle and upper parts of the Hypselum Zone. This change in the character of the radiolarian assemblages suggests Boreal influences into the Submediterranean basin related to activity of sea currents, which have been stimulated by climatic changes during the latest Oxfordian.
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