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Wyświetlanie 1-8 z 8
Tytuł:
Geochemical study of precipitates in the architectural surfaces from Bern, Switzerland
Autorzy:
Huber, Miłosz Andrzej
Hałas, Stanisław
Powiązania:
https://bibliotekanauki.pl/articles/763337.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej
Tematy:
precipitates
sulfate
geochemistry
pollution
microscopy
isotope analysis
Opis:
This geochemical study aims to resolve genesis of precipitation spots on the walls on the Nydeggbrücke in Bern, Switzerland. The bridge is composed of Jurassic limestone and dolomites and coated on both sides with Miocene flysch sandstone. As a result of infiltration of aqueous solutions derived directly from the road embankment into the sandstone, sulfate encrustation on the walls of sandstone has been formed.The study of these precipitates using optical and electron microscopy clearly shows dominant sulfate phases are gypsum (calcium sulfate), mirabilite (sodium hydrated sulfate) and polyhalite (potassium, calcium and magnesium sulfate). Impurities of Ni, Cu, Zn and Pb was encountered by ICP-MS analysis. Identified polymetallic mineralization is associated with the infrastructure of the bridge and the accumulation of pollution from vehicular traffic. This is also confirmed by sulfur and oxygen stable isotope analyses of sulfates.
Źródło:
Annales Universitatis Mariae Curie-Skłodowska, sectio AAA – Physica; 2015, 70
0137-6861
Pojawia się w:
Annales Universitatis Mariae Curie-Skłodowska, sectio AAA – Physica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Element enrichment and provenance of the detrital component in Holocene sediments from the Western Black Sea
Autorzy:
Dekov, V.M.
Darakchieva, V.Y.
Billstrom, K.
Garbe-Schonberg, C.D.
Kamenov, G.D.
Gallinari, M.
Dimitrov, L.
Ragueneau, O.
Kooijman, E.
Powiązania:
https://bibliotekanauki.pl/articles/2079273.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
trace element concentration
isotope analysis
enrichment factor
Holocene sediment
catchment area
geochemical analysis
Black Sea
Opis:
Concentrations of a large set of major and trace elements, and Sr, Nd and Pb isotope ratios were measured in Holocene sediments cored in the western deep Black Sea in order to unravel: (1) the controls of element enrichment, and (2) sources of the detrital component. The transition of the basin from oxic to euxinic resulted in enrichment or depletion in a number of elements in the deep-sea sediments. Authigenic Fe enrichment appears to depend on the amount of Fe mobilized from the sediment through the benthic redox shuttle mechanism and free H2S in the water column (degree of “euxinization”). Manganese enrichment is controlled by diagenetic reactions within the sediment: the dissolution of Mn minerals, Mn2+ diffusion upward and reprecipitation. Barium enrichment is also controlled by diagenetic reactions, sulfate reduction and methanogenesis, that take place above and below the sulfate-methane transition, respectively. The major part of V, Co, Ni, Cu, Zn, Cr, Mo, Cd and Sb is inferred to have co-precipitated with Fe in the euxinic deep waters and to have been incorporated into authigenic Fe-sulfides. Basin reservoir effect additionally influences the Mo enrichment. The U enrichment is interpreted to have a different origin in the two organic-rich stratigraphic units (II and I). It is inferred to be: (i) at the expense of the U inventory of the deepwater pool and a result of inorganic reduction of U at euxinic conditions in the lower Unit II; and (ii) at the expense of the U inventory of the surface water pool and a result of biogenic uptake and transfer to the sediment by the plankton in the upper Unit I. The high field strength elements are closely linked to the detrital component and their depletion in the organic-rich sediments reflects a dilution of the detrital component by the biogenic one. The enrichments of REE, Sn and Th are likely controlled by adsorption on clay minerals. Sr-Nd-Pb isotope compositions of the alumino-silicate component of the studied sediments are relatively uniform. They are most likely controlled by riverine suspended matter supplied mainly in the NW Black Sea (Danube Delta) and transported southward by marine currents, and to a lesser degree by suspended matter from the small rivers draining SE Bulgaria and NW Turkey. Wind-blown dust from the Sahara Desert appears to have a minor contribution to the alumino-silicate component of the sediments. The slight shift in the Pb isotopes in Unit I upper layers is possibly caused by the addition of anthropogenic Pb.
Źródło:
Oceanologia; 2020, 62, 2; 139-163
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zastosowanie badań izotopowych do określania pochodzenia wybranych biomarkerów
Application of isotope analyses for determination of the origin of selected biomarkers
Autorzy:
Bieleń, Wojciech
Janiga, Marek
Powiązania:
https://bibliotekanauki.pl/articles/2143240.pdf
Data publikacji:
2022
Wydawca:
Instytut Nafty i Gazu - Państwowy Instytut Badawczy
Tematy:
spektrometria masowa
analiza izotopowa
biomarkery
pristan
fitan
substancja źródłowa
mass spectrometry
isotope analysis
biomarkers
pristane
phytane
organic matter
Opis:
Badania izotopowe n-alkanów, pristanu (Pr) oraz fitanu (Ph) przeprowadzono przy pomocy aparatu GC-IRMS. Porównanie wartości δ13C – pristanu do n-C17 oraz fitanu do n-C18, a także zestawienie wartości δ13C pomiędzy pristanem a fitanem w obrębie jednej próbki pomaga zidentyfikować źródło pochodzenia tych izoprenoidów, co było celem pracy. Ta ostatnia informacja uwiarygadnia lub podaje w wątpliwość wskaźnik środowiska sedymentacji – Pr/Ph. Wartości δ13C n-alkanów dla rop naftowych z tego samego złoża: Bóbrka 113, Niepodległość 2, Bandrów wskazują na pochodzenie tych rop od roślin C3 (fotosynteza typu C3) oraz z osadów rzecznych lub/i jeziornych. N-alkany występujące w tych trzech ropach naftowych mogą mieć mieszane źródła i pochodzić zarówno od roślin lądowych, jak i wodnych. Ropa naftowa Łodyna 90K może pochodzić z różnorakich wyższych roślin. Wartości δ13C n-alkanów z próbek ekstraktów bitumicznych Dukla 2A i Dukla 2D są charakterystyczne dla roślin C3. Pristan i fitan w badanych próbkach rop naftowych i w przypadku dwóch próbek ekstraktów bitumicznych Dukla 2A i Dukla 2D mają wartości δ13C niższe niż wartości δ13C dla n-C17 i n-C18, co sugeruje pochodzenie od organizmów heterotroficznych. We wszystkich badanych próbkach rop naftowych (wyjątki: Łodyna 90K, Osobnica 35) wartości δ13C dla Pr i Ph w obrębie pojedynczej próbki świadczą o tym samym materiale źródłowym dla tych izoprenoidów. Ta informacja potwierdza, że wskaźnik Pr/Ph, mówiący o typie środowiska sedymentacji materii organicznej, jest wiarygodny. W dwóch ekstraktach bitumicznych (Dukla 2D i Krosno 8) wartości δ13C dla Pr i Ph są różne, dlatego istnieje duże prawdopodobieństwo odmiennego pochodzenia dla tych dwóch izoprenoidów (należy być ostrożnym co do wiarygodności wskaźnika środowiska sedymentacji Pr/Ph).
Isotope analysis of n-alkanes, pristan (Pr) and phytane (Ph), were carried out on the GC-IRMS apparatus. Comparing the δ13C values of pristan to n-C17, phytane to n-C18 and pristan to phytane within one sample helps to identify the source of these isoprenoids. The latter information legitimises or questions the sedimentation environment index – Pr/Ph. The values of δ13C of n-alkanes for crude oil from one field: Bóbrka 113, Niepodległość 2, Bandrów indicate the origin of C3 plants (photosynthesis type C3) and river and / or lake sediments. The N-alkanes found in these three crude oils could have been sourced by organic matter from terrestrial and aquatic plants. Łodyna 90K crude oil was derived from a variety of higher plants. The δ13C values of n-alkanes for samples Dukla 2A and Dukla 2D bituminous extracts are characteristic for C3 plants. Pristan and phytan in the analyzed crude oil samples and in the case of two samples Dukla 2A and Dukla 2D bituminous extracts have δ13C values lower than the values of n-C17 and n-C18, which suggests their origin from heterotrophic organisms. In all analyzed crude oil samples (exceptions: Łodyna 90K, Osobnica 35) the δ13C values of Pr and Ph within a single sample indicate the same source material for these isoprenoids. This information confirms that the Pr/Ph ratio is reliable. In two bituminous extracts (Dukla 2D and Krosno 8) the δ13C values of Pr and Ph are different, therefore there is a high probability of different origins for these two isoprenoids (the Pr/Ph ratio may be unreliable).
Źródło:
Nafta-Gaz; 2022, 78, 5; 336-342
0867-8871
Pojawia się w:
Nafta-Gaz
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ingresje i ascenzje wód słonych na Pobrzeżu Słowińskim
Ascension and ingression of saline waters of the Pobrzeże Słowińskie Region
Autorzy:
Krawiec, A.
Powiązania:
https://bibliotekanauki.pl/articles/2075392.pdf
Data publikacji:
2015
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
ingresja i ascenzja
analiza izotopowa
geneza wód podziemnych
wiek wód podziemnych
wybrzeże Bałtyku
ascension and ingression process
isotope analysis
groundwaters genesis and ages
Baltic coast
Opis:
The paper presents comprehensive results of the hydrogeochemical and isotope analysis of waters in terms of their genesis and “ages”. Mostly chloride anomalies were found on the Polish Baltic coast. The processes of ascension and ingression of saline and brackish waters are the main reasons for their development. The water exchange rate was determined in each aquifer systems within the study area the results of isotope analysis, the concentrations of 4He and 3H. A significant contribution of infiltrating waters in cold climate is apparent in samples taken from: Ustka, Jarosławiec and Dąbki, for which NGT values range from 4.3 to 5.2°C. Waters with this genesis are found mainly in deep Pleistocene aquifers and Cretaceous roof layers. Changes in the chemical composition of waters in this area are strongly affected by human activity consisting in excessive exploitation of aquifers (mainly in the 1970s and 1980s). The process of saline water penetration into exploited aquifers was most extensive at that time. At present, it has been significantly inhibited as a result of reduced water extraction at the water intakes in this area. New water intakes are located at a considerable distance from the areas threatened with ingression or ascension of brine and saline water.
Źródło:
Przegląd Geologiczny; 2015, 63, 10/1; 867--872
0033-2151
Pojawia się w:
Przegląd Geologiczny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Carbon and oxygen isotope variability among foraminifera and ostracod carbonated shells
Autorzy:
Fourel, François
Martineau, François
Emoke Tóth, Emoke
Görög, Agnes
Escarguel, Gilles
Lécuyer, Christophe
Powiązania:
https://bibliotekanauki.pl/articles/763395.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Marii Curie-Skłodowskiej. Wydawnictwo Uniwersytetu Marii Curie-Skłodowskiej
Tematy:
stable isotope
foraminifera
ostracod
heterogeneity
single shell analysis
Opis:
This study investigates the effect of biological and environmental inter-individual variability on the meaning of d18O and d13C values acquired on small carbonated shells. First we present data obtained with a MultiPrep automated carbonate system on small sample sizes of a homogeneous carbonate material: Carrara marble. This demonstrates the capacities of the analytical system to reliably run small amounts of carbonates even down to 10 mg. Then we present two data sets obtained on real fossil samples of various size (sensu number of individual organisms) calibrated against the NBS19 carbonate standard. Both datasets evidence a clear trend of between-biological sample standard deviation increase for both d18O and d13C measurements when the number of pooled specimens per sample decreases. According to the results obtained from a systematic study of a geologically homogeneous sample of coeval fossil Elphidium foraminifera, we estimate that there is 95% of chances to reach between-biological sample standard deviation values higher than 1.02‰ (d18O) and 1.45‰ d13C) based on single-cell measurements. Such values are one order of magnitude higher than the instrumental standard deviations associated with these stable isotope ratios. Conversely, a minimum of 35 (d18O) and 44 (d13C) pooled specimens of Elphidium appears necessary to reach a between-sample standard deviation £ 0.25‰ with a probability of 95%. Such biological intrinsic and irreducible variability between coeval individuals, and thus samples, clearly questions the interest for single-cell analyses, more precisely, for coastal marine species, such as Elphidium, subject to many environmental changes during their life-time. Indeed, strong variations in salinity or temperature, as well as biogenic fractionation, could influence the isotopic composition of an individual specimen. Results might be less problematic for an average community including several tests. This paper underlines uncertainties linked to specific environments in which selected organisms live, especially for paleoceanographic or paleoclimatic reconstruction purposes where secular oxygen and carbon isotope variations typically range from 0.5 to 1.5‰.
Źródło:
Annales Universitatis Mariae Curie-Skłodowska, sectio AAA – Physica; 2015, 70
0137-6861
Pojawia się w:
Annales Universitatis Mariae Curie-Skłodowska, sectio AAA – Physica
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:
Limitation of lignin derivatives as biomarkers of land derived organic matter in the coastal marine sediments
Autorzy:
Pempkowiak, J.
Powiązania:
https://bibliotekanauki.pl/articles/2079190.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
lignin oxidation
biomarker
stable carbon isotope
nonlinear analysis
Gdansk Bay
Southern Baltic Sea
coastal sediment
Opis:
Lignin oxidation products (vanillyl, syringil and cummaryl phenols), and δ13C were measured in a variety of land and marine samples collected in Inner Puck Bay – dominated by marine vascular plants, small river run-off, and shallow bottom, and in Gdańsk Bay – characterized by large river run-off, small marine vascular plants population, and the average depth exceeding euphotic zone. Both study areas are parts of the Gdańsk Basin, Southern Baltic. Typical δ13C values (δ13C = -28‰) and both composition and concentrations of lignin phenols were measured in samples originating from land. Small, yet easily measurable amounts of lignin phenols were found in marine vascular plants biomass (Σ8 = 90 µg/100 mg organic matter). The biomass was characterized by exceptionally high δ13C values (-12‰). No lignin phenols and typical δ13C values (-22‰) were measured in marine phytoplankton biomass. δ13C and both composition and content of lignin phenols in organic matter of surface sediments collected in the study area fall in the range marked by the end members. The proportion of land derived organic matter calculated using lignin phenols, or δ13C in Gdańsk Bay were comparable, while in Puck Bay they differed substantially. It was concluded that a) in areas with substantial bottom coverage with vascular plants the two end members approach, usually employed to establish the contribution of organic matter sources, is insufficient, b) organic matter originating from three sources: riverine, phytoplankton, and vascular plants contribute to sedimentary organic matter in Puck Bay with the respective proportion 30:40:30.
Źródło:
Oceanologia; 2020, 62, 3; 374-386
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zmiany klimatu w plejstocenie w świetle danych palinologicznych
Pleistocene climate changes based on palynological data
Autorzy:
Granoszewski, W.
Winter, H.
Powiązania:
https://bibliotekanauki.pl/articles/2075572.pdf
Data publikacji:
2016
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
plejstocen
morskie stadium izotopowe
interglacjał
interstadiał
glacjał
analiza pyłkowa
Pleistocene
Marine Isotope Stage
interglacial
interstadial
glacial
pollen analysis
Opis:
The paper presents general climate changes during the last 2.6 Ma in the Northern Hemisphere. Plant formations of warm intervals (interglacials and interstadials) are briefly described. Disappearance of some more climate-sensitive tree taxa as well as climate changes during the Pleistocene in Northern Europe are also portrayed.
Źródło:
Przegląd Geologiczny; 2016, 64, 1; 43--48
0033-2151
Pojawia się w:
Przegląd Geologiczny
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-8 z 8

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