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EN
Ordovician was an extremely turbulent period for the Earth system, where the Great Ordovician Biodiversification Event (GOBE) occurred in the early-middle Ordovician. Many hypotheses were proposed, taking into account both biotic and abiotic factors. One such hypothesis posits that global cooling led to a transition from greenhouse to icehouse climate systems, which further triggered feedback mechanisms such as increased oceanic circulation, bio-productivity, and oxygenation during the middle Ordovician. Direct evidence, however, is still scarce. Here, we have compiled a comprehensive dataset of δ18O (10,636) from carbonate rocks and fossil shells as well as clumped isotope temperature data (Δ47; 88) spanning the entire Ordovician. Our study investigates climate change from both temporal and spatial perspectives. We assessed the effects of the late diagenesis alteration, lithological differences, different depositional environments and water depths on the carbonate δ18O, and corrected the latitudinal effect of the δ18O in seawater. The latitudinal temperature gradient (LTG) was introduced to account for the spatial patterns of climate change, which here refers to the difference in sea-surface temperature between low (<20°) and low-to-middle (20–40°) latitudes. We observed a gradual increase in the LTG from Tremadocian to Dapingian, indicating an amplified thermal contrast between low and low-middle latitudes. It suggested a remarkable climate cooling and shift towards an icehouse climate state, coinciding with the GOBE. From Darriwilian to Sandbian, the LTG weakens significantly and the temperature difference decreases, which is consistent with the plateau of global temperatures and the slow change in species diversity. After Sandbian, a progressive steepening of LTG was observed, which provides the first evidence for low paradoxical atmospheric CO2 at the Late Ordovician. Our study supports the global cooling hypothesis and sheds light on the links between climate change and biological evolution across the Ordovician.
EN
The Guelma-Bouchegouf irrigated perimeter uses water from the Bouhamdane dam between May and the end of October. It should be noted that the water is channelled to the perimeter via Seybouse Wadi, which serves as a water collector. The water is supplied during the dry season, which causes water pollution due to strong evaporation and industrial discharges. Moreover, during the summer period irrigation increases since the crops grown are industrial tomatoes, melon, watermelon and beans, requiring intense and sustained watering. The measurement of the conductivity of the water flow shows a clear increase from 3000 μs/cm to 6000 μs/cm. This increase is connected to interactions between water and rock, compounded by the adverse impact of climate change. It should be noted that during this period the average temperature is 26°C and sometimes temperature values exceeding 40°C are recorded. In addition, industrial discharges into the Seybouse Wadi occur without pre-treatment, leading to water pollution by heavy metals. The results of the analyzes of the Seybouse Wadi waters show the presence of pollutants such as iron, manganese, zinc, copper and nutrients in the upstream zone (Guelma region). In the downstream area (Annaba) we notice the presence of pollutants such as chromium, lithium, iron, manganese and nutrients.
PL
Celem pracy było opracowanie i zwalidowanie metody oznaczania zawartości itru w eluatach uzyskiwanych z kolumn zawierających żywicę DGA, w celu sprawdzenia jej właściwości pod kątem powinowactwa do itru i stopnia jego zatrzymywania. Wykorzystana została technika optycznej spektrometrii emisyjnej ze wzbudzeniem w plazmie indukcyjnie sprzężonej (ICP-OES).
EN
The oldest Jurassic (Kimmeridgian) Plattenkalk occurs in Wattendorf on the northern Franconian Alb (southern Germany). It is a 15 m thick alternation of laminated dolomite and limestone, interbedded with carbonate debris layers in a depression ~2 km across and a few tens of metres deeper than the surrounding microbial-sponge reefs. The Plattenkalk overlies a few tens of metres of microbialsponge biostrome facies and bedded, micritic basinal limestone. The bulk-rock stable isotopes of the micritic basinal facies gradually change from normal marine (δ13C ~ +2‰, δ18O ~ –2‰ VPDB) to lower values (δ13C ~ 0‰, δ18O ~ –6‰) in a ~ 40 m thick interval including Plattenkalk and suggest ageing of the bottom waters. The surrounding reefs are isotopically nearly invariant (δ13C ~ +2‰, δ18O ~ –2‰ VPDB). An isotope anomaly (δ13C of > ~ –9‰) is restricted to the basinal facies and is most pronounced in the biostrome facies. This indicates methanogenesis, which is documented in negative δ13C in dedolomite, calcite-cemented dolomite and calcite concretions and occurred probably mainly below seabed. The Konservat-Lagerstätte was probably deposited near an oxygen minimum zone in a water column with low productivity of organic material. Dolomite is in isotopic equilibrium with Plattenkalk and was probably deposited as protodolomite from chemically modified, aged seawater. 87Sr/86Sr ratios of bulk carbonate are often slightly radiogenic, probably due to random analytical sample contamination by clay minerals. Belemnite and some matrix 87Sr/86Sr is slightly lower than that of Kimmeridgian seawater, either caused by basin restriction or by fluids derived from the diagenesis of Oxfordian rocks below. An equivalent Upper Kimmeridgian depression ~23 km distant and a somewhat younger Konservat-Lagerstätte in Poland show a δ13C isotope anomaly below the main fossil beds. Isotopic evidence for saline bottom waters, the current interpretation, is lacking. This study also shows that micritic carbonates can preserve their early diagenetic, marine δ18O signal, which is correlatable over tens of kilometres
PL
Systemy wspomagania decyzji cieszą się coraz większą popularnością ze względu na szybkie dostarczanie informacji o rozwoju sytuacji radiacyjnej po awarii jądrowej z uwolnieniem izotopów promieniotwórczych do powietrza atmosferycznego. Systemy te są wykorzystywane jako narzędzie bezpośrednio stosowane w sytuacji awaryjnej oraz jako narzędzie do przeprowadzenia przed inwestycyjnych obliczeń z zakresu planowania awaryjnego. Artykuł przedstawia podstawowe funkcjonalności systemu wspomagania decyzji RODOS. Program służy do przeprowadzania prognoz rozwoju zdarzeń radiacyjnych z uwolnieniem izotopów promieniotwórczych do atmosfery w wyniku awarii w elektrowniach jądrowych.
EN
Decision support systems are increasingly popular due to the fast delivery of information about development of the situation during the nuclear accidents. The information provided by decision support systems facilitate proper selection of necessary protective actions and correct allocation of services involved in the activities. The RODOS system is designed for forecasting the dispersion of radioactive isotopes in the atmosphere. It can be used in case of real radiological nuclear emergency as well as for emergency preparedness purpose.
EN
Three-dimensional modeling of the limestone and dolomite distribution in an Upper Permian (Zechstein) stromatolite-bryozoan reef, ~500 m in diameter and 35 m thick (77 borehole cores, 172 data points), shows that dolomite occurs as laterally and vertically discontinuous intervals. The prevailing mineral phases are near-stoichiometric dolomite and Mg-free calcite (370 XRD and 274 XRF analyses). Both δ13C and δ18O (526 analyses) show a spread of ~10‰ and co-vary with the mineralogy; the heaviest dolomite and calcite δ13C differ by ~1.5‰. Diagenetic modifications caused by flowing meteoric fluids could account for the observed “inverted J” trend of stable and the radiogenic signature of 87Sr/86Sr (23 analyses), but neither vertical nor horizontal gradients occur in the reef modeled. Because the dolomite geometries are incompatible with those predicted by fluid flow models, and the limestone-dolomite difference in δ13C overlaps estimates of isotope fractionation associated with Mg content, the dolomite studied was a depositional Very High Mg Calcite recrystallized to dolomite in a semi-closed diagenetic system rather than a Low Mg Calcite transformed by a dolomitization process. The isotope pattern suggests biogenic fractionation and/or loss of heavy stable C and O and light Sr isotopes during diagenesis.
8
Content available remote Isotopic composition of precipitation in Poland: a 44-year record
EN
Isotopic composition of precipitation (2H/1H and 18O/16O isotope ratios, tritium content) is nowadays widely used in numerous applications of environmental isotopes—most notably in hydrology, climatology and biogeochemistry. Here we present a long record (44 years) of stable isotope composition and tritium content in monthly precipitation available for the Krakow station (southern Poland). Krakow is the only site in Poland for which long-term record of the isotopic composition of monthly precipitation is available. The tritium data are discussed here in the context of generally declining levels of bomb tritium in the global atmosphere and growing influence of technogenic emissions of this isotope. Two aspects of temporal variability of stable isotope composition of precipitation collected in Krakow are discussed here: (i) seasonality and (ii) interannual changes of δ18O and δ2H signal. Whereas the seasonality of stable isotope signal is generated mainly by seasonally varying the degree of rainout of air masses bringing moisture from the source regions (subtropical Atlantic Ocean) to the centre of the European continent, the North Atlantic Oscillation seems to govern interannual changes of δ18O and δ2H on the decadal timescale. Progressing warming of the local atmosphere, in the order of 1.8 °C in the past four decades, leaves its imprint in stable isotope signal measured in Krakow precipitation; the slope of isotope–temperature relationship is in the order of 0.50‰/°C for δ18O and 3.5‰/°C for δ2H.
EN
Morphostructural, hydrogeological and hydrochemical approaches were applied to Hammamet plain and its surrounding mountains in the eastern part of Algeria to characterize the groundwater system and its potential for exploitation. The Essen and Troubia Mountains form the natural boundaries of Hammamet plain. The objective of this study is to utilize remote sensing techniques combined with structural analysis, hydrogeology and hydrogeochemistry to identify the potential fracture zones for groundwater in the strongly fractured and karstified deep aquifers. The delineated zones of potential groundwater resources are verified by detailed hydrogeological field surveys. From a hydrogeological point of view, these two mountains, constitute a unit limited by faults oriented ENE-WSW, NNW-SSE and NNE-SSW. Specifically, fractures of the latter two directions influence the compartmentalization and the hydrogeological functioning of this unit. According to the degree of fracturing and/or karstification, two basic types of aquiferous behaviour have been distinguished: fissured aquifer (Essen Mountain and Troubia Mountain), and porous aquifer (Hammamet plain). The study of the hydrochemical characteristics of groundwater samples shows that the majority of samples are mainly of HCO3– and Ca2+ water type. The ionic speciation and mineral dissolution/precipitation was calculated with the PHREEQC software. The chemical composition of the water is influenced by the dissolution and/or precipitation processes during the water–rock interaction and by the cationic exchange reactions between groundwater and alluvial sediments. The high content of CO2 in the water samples suggests that they circulate in a geochemical open system. The isotopic analysis of some groundwater samples shows a similarity with the meteoric waters, which reflect their short residence time and a low evaporation of the infiltrated water.
PL
Celem scharakteryzowania systemu wód podziemnych oraz możliwości eksploatacji tych wód zastosowano metody morfologiczne, hydrogeologiczne i hydrochemiczne na równinie Hammamet i otaczających ją górach we wschodniej części Algierii. Góry Essen i Troubia tworzą naturalną granicę równiny Hammamet. Przedmiotem badań była identyfikacja możliwych stref szczelin w silnie spękanym i głębokim, krasowym poziomie wodonośnym z zastosowaniem technik teledetekcji w połączeniu z analizą strukturalną, hydrogeologią i hydrogeochemią. Wytyczone strefy potencjalnych zasobów wód gruntowych weryfikowano w szczegółowych hydrogeologicznych badaniach terenowych. Z hydrogeologicznego punktu widzenia wymienione góry stanowią jednostkę ograniczoną przez uskoki ułożone wzdłuż linii ENE-WSW, NNW-SSE i NNE-SSW. Szczeliny w dwóch ostatnich kierunkach wpływają na podział i hydrologię tej jednostki. Według stopnia spękania i/lub postępu procesów krasowych wyróżniono dwa główne typy poziomów wodonośnych: poziom spękany (góra Essen i góra Troubia) oraz poziom porowaty (równina Hammamet). Badanie hydrochemicznych właściwości próbek wody gruntowej wykazało, że są one zdominowane przez HCO3– i Ca+2. Skład jonowy i procesy rozpuszczania/wytrącania obliczano za pomocą programu PHREEQC. Na skład chemiczny wody wpływają procesy rozpuszczania i precypitacji w czasie oddziaływań między wodą a podłożem skalnym oraz wymiana kationów między wodą gruntową a aluwialnymi osadami. Duże stężenie CO2 w próbkach wody sugeruje, że krąży ona w systemie otwartym. Analiza izotopowa niektórych próbek wody wykazuje ich podobieństwo do wód opadowych, co uwidacznia się w ich krótkim czasie retencji i niewielkim parowaniu wód infiltracyjnych.
10
Content available remote Characterization of some selected mud volcanoes of southern Taiwan
EN
In the present study, some mud volcanoes in Pingtung and Kaohsiung areas were selected. The selected mud volcanoes are located above the mud diaper system in southern Taiwan. Three different sampling techniques were used to collect samples in and around the said mud volcanoes. The results show that river water samples from different places fall on the meteoric line. Mud samples are found to be heavier in oxygen isotope while hydrogen isotope remains the same. Soil gas samples were also collected at the depth of 1 m and dissolved gases from the mud volcanic site (or nearby) were collected for gas chromatography analyses. Soil gas samples and dissolved gas from mud pool and groundwater were analyzed for radon concentration using RAD7 (solid-state nuclear track detector) bi-weekly. Long-term investigation will be needed to understand the relationship of mud volcanoes the eruption cycle with gas composition variations. It will also help to understand their relationship with tectonic activities in the region.
EN
The paper contains the results of analysis of chemical, isotopic and trace metal composition of anomalous spring water in the Tatra Mts. Obtained data were the basis for an attempt to determine the origin of this hydrogeochemical anomaly. The spring is located in the Tomanowa Valley in the Western Tatra Mts. The spring water is characterized by the mineralization (TDS) above 500 mg/dm3. As regards the chemical composition of the water, Ca2+ ions show the highest concentration among cations, while HCO- among anions. The spring water has been assigned to the: SO —HCO—Ca-Mg hydrochemical type. Among trace metals, Sr, Ba, B, Li and Al. reveal The highest concentrations. The oxygen and hydrogen isotopic composition(δ18O and δ2H) indicates that this is infiltration water. Delta values of oxygen and sulphur isotopes (δ18OS and δ34S) of the sulphate ion indicate that SO4 of this spring water is likely derived from leaching of gypsum or anhydrite evaporites.
EN
The present study assesses the physico-chemical character of the fluids responsible for the genesis of carbonate minerals in the Middle Jurassic sideritic rocks at the northeastern margin of the Holy Cross Mts. and in the Częstochowa region. These rocks occur at present at depths between 30 and 600 m. Fluid inclusion and isotopic analyses have been performed in the carbonate minerals from sideritic sandstones, clayey siderites and sideritic coquinas. Siderite is the main carbonate mineral of the sideritic rocks. Calcite and ankerite are also present. The siderite is represented by two varieties, Mg-rich siderite (sideroplesite, less commonly – pistomesite) and siderite. Two generations of siderite have been distinguished – an early and a late one. The early siderite was formed at temperatures of about 20°C in the zone of microbiological methanogenesis from marine waters with some influence of meteoric waters (δ18O from –7.84 to –1.92‰ VSMOW). The late siderite crystallized at temperatures of about 62–110°C from pore waters enriched in 18O (δ18O >0‰ VSMOW) as compared with the isotopic composition of the waters responsible for the early siderite generation. The conducted fluid inclusion analyses point to formation of the cements from complex fluids of brine and carbon dioxide character, with densities slightly exceeding 1 g/cm3 and salinities varying from 10.5 to 16.9 wt.% NaCl eq. and from 6.4 to 14.0 wt.% NaCl eq. in the Holy Cross Mts. and in the Częstochowa region, respectively. The homogenization temperatures lie in the intervals of 62–110°C and 60–97°C, respectively and represent elevated values compared with data from the Polish Lowlands. Apart from burial, other heat sources must have been important for the lithogenesis of the Middle Jurassic deposits.
PL
Z badań składu chemicznego i izotopowego wód górnojurajskiego poziomu wodonośnego rejonu Buska-Zdroju i Solca- Zdroju wynika, że są to solanki pierwotne i wody słone, zasilane w okresie przedplejstoceńskim, kiedy klimat charakteryzował się długimi okresami znacznie cieplejszymi niż współcześnie. Solanki te mają zdecydowanie cięższy skład izotopowy niż wody lecznicze, siarczkowe występujące na tym obszarze w utworach kredowych (głównie cenomanu) oraz zbliżone wartości wskaźników hydrochemicznych do wód morskich.
EN
The study of the chemical and isotopic composition of the Upper Jurassic aquifer in the Busko-Zdrój and Solec-Zdrój region suggests primary nature of the brines supplied before the Pleistocene under climate conditions characterized by long and much warmer periods than today. Compared to the sulphide healing waters occurring in the Cretaceous formations, mainly of Cenomanian age, the discussed brines and salt water are characterized by a far heavier isotopic composition as well as by the values of hydrochemical indica¬tors mostly similar to those of marine waters.
EN
The quality of palaeoenvironmental reconstructions based on macrofossil carbonate critically depends on preservation of the shell material because post-depositional processes can modify its structural, chemical and isotopic composition, potentially overprinting or completely erasing palaeoenvironmental information. A suite of methods can be employed to evaluate the impact of diagenetic processes on the primary geochemical signatures of samples. Here we review the benefits and shortcomings of the most commonly employed optical (optical microscopy, cathodoluminescence microscopy, scanning electron microscopy) and chemical (trace element abundances, isotopic ratios) screening techniques used to assess the alteration degree of low-Mg calcite macrofossils and summarize the findings on diagenetic trends observed for elemental and isotopic systems in such materials. For a robust evaluation of the preservation state of biogenic calcite, it is advisable to combine a set of complementary techniques. Absolute limiting values of element and isotope ratios for discarding diagenetically altered materials cannot be universally applied, but should rather be evaluated on a case to case basis. The evaluation can be improved by analyses of diagenetic carbonate and altered fossil materials, which help constraining the diagenetic trajectories in the sampled specimens. Quantification of post-depositional alteration is possible, but in most cases the complexity of diagenetic systems hampers the possibility of retrieving original proxy values for palaeoenvironmental reconstructions from partially altered materials.
PL
Artykuł przedstawia aktualne wymagania dotyczące zawartości naturalnych izotopów i pierwiastków promieniotwórczych w surowcach i materiałach stosowanych w budynkach oraz możliwości ich spełnienia przez ceramiczne wyroby budowlane. W artykule przedstawiono aktualne wyniki badań ceramicznych elementów konstrukcyjnych w zakresie promieniotwórczości naturalnej.
EN
This article presents current requirements for content of natural radioactive isotopes in raw materials and building materials. The article includes current research results in the field of natural radioactivity of clay masonry units.
EN
The fruiting bodies of fungi sprout from mycelium are capable of accumulating significant amounts of trace elements, both metals and metalloids. Content of these elements in fruiting bodies may exceed their concentration in the substrate where fungi develop. Among the elements the radioactive nuclides are also present. In this work health risk caused by increased radioactivity dose absorbed with Xerocomus badius bay bolete consumption was estimated. In analysis concentrations of radioactive isotopes 137Cs and 40K were taken into consideration. It was found that moderate ingestion of bay bolete does not create health risk due to increased radioactive substances intake. The amount of consumed mushrooms that could deliver the dose exceeding the safe one, is rather improbable in real life.
PL
Owocniki grzybów wyrastające z grzybni są zdolne do gromadzenia znacznych ilości pierwiastków śladowych zarówno metali, jak i niemetali. Zawartość tych pierwiastków w owocnikach może wielokrotnie przekroczyć ich stężenia w podłożu. Wśród pochłoniętych pierwiastków są również nuklidy promieniotwórcze. Dokonano oceny potencjalnych dawek skutecznych promieniowania gamma w wyniku wchłonięcia 137Cs i 40K wraz ze spożywanym grzybem. Na podstawie wyników pomiarów stwierdzono, że umiarkowane spożycie podgrzybka brunatnego nie stwarza zagrożenia dla zdrowia ze względu na zwiększone spożycie substancji radioaktywnych.
17
Content available remote From the discovery of radioactivity to the development of the K-Ar dating method
EN
In this paper I try to explain why the potassium-argon dating method was developed much later than other radiometric methods (like U-He and U-Pb), which were established at the beginning of the 20th century. In fact the pioneering paper by Aldrich and Nier (1948) was published 50 years after the discovery of polonium and radium, when nearly all the details concerning potassium isotopes and radioactivity of potassium-40 had been investigated. The role of Marie Curie’s concept of the na-ture of radioactivity in the discovery of the radioactivity of potassium is emphasized.
PL
Celem artykułu jest przedstawienie aktualnego stanu wiedzy na temat oznaczeń trwałych izotopów ołowiu oraz możliwości wykorzystania wyników badań w różnych dziedzinach nauki. Skład izotopowy ołowiu oznaczany w różnych próbkach (np. środowiskowych, medycznych, artefaktach archeologicznych) może służyć wyjaśnieniu problemów naukowych z zakresu ochrony środowiska, geologii, kryminalistyki, archeologii, ekologii, nauki o żywieniu i in. Popularność badań trwałych izotopów ołowiu wynika, między innymi, z coraz lepszego dostępu do nowoczesnych technik analitycznych pozwalających na precyzyjny pomiar stężeń izotopów (TIMS, MC-ICP-MS, LA-ICP-MS i in.). W niniejszym artykule skrótowo omówiono metodykę oznaczania trwałych izotopów ołowiu oraz podano przykłady badań stosunków izotopowych ołowiu w różnych dyscyplinach naukowych.
EN
The aim of this paper is to present the current knowledge on determination of stable lead isotopes and to discuss the possibility of their application in different scientific disciplines. Lead isotope ratio determined in different kinds of samples (e.g. environmental samples, medical samples, artifacts) may be useful for elucidation of scientific problems in environmental sciences, geology, criminology, arheology, ecology, nutrition sciences etc. Growing popularity of lead isotope ratio studies results from facilitate access to modern analytical techniques that enable precise isotope measurements (TIMS, MC-ICP-MS, LA-ICP-MS etc.). This article briefly discusses the methods used in stable lead isotope determinations and gives examples of the studies carried out by researchers specializing in different scientific disciplines.
PL
Termin izotop pochodzi z języka greckiego (izos-topos) i oznacza "to samo miejsce". Odnosi się to do miejsca, "tego samego", które zajmuje dany pierwiastek w układzie okresowym. Izotopy to odmiany pierwiastka chemicznego różniące się liczbą neutronów w jądrze atomu. Izotopy możemy podzielić na dwie podstawowe grupy : izotopy stabilne i nietrwałe (radioaktywne).
EN
Studies of the Middle Miocene sandstones in selected wells from the western Ukraine concerned calcite cements, both from isotopic and fluid inclusion aspects. The aim of the reconnaissance study was to find out inclusion – isotopic constraints for the calcite cements in the sandstones. The studied sandstones are subarkosic, sporadically sublithic arenites. The delta1318
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