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Wyświetlanie 1-12 z 12
Tytuł:
Antropogeniczne przeobrażenia oerodowiska geochemicznego aluwiów Zagożdżonki [Puszcza Kozienicka]
Anthropogenic changes of geochemical environment in Zagożdżonka river alluvium sediments [Central Poland]
Autorzy:
Lis, J.
Parafiniuk, J.
Pasieczna, A.
Powiązania:
https://bibliotekanauki.pl/articles/2074509.pdf
Data publikacji:
2007
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
alluvium
geochemistry
Polska
Opis:
The paper presents detailed geochemical survey of stream sediments in Zagożdżonka river system. The Zagożdżonka river drains agricultural areas and forests [Puszcza Kozienicka] and flows through towns-Pionki and Kozienice. The works [metallurgical, power plants, plastic materials, munitions-factory localized in towns put industrial and communal sewage into Zagożdżonka river. Active sediments (180 samples; <0.2 mm) were leached with HCl (1:4); then, using the ICP-AES method determinations were made the concentration of Ag, Al, As, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, P, Pb, S, Sr, Ti, V and Zn. Mercury concentration was measured using the CV-AAS method. The geochemical survey reveals that industrial plants activity are the main sources of anthropogenic pollution of stream sediments in Zagożdżonka river catchment. The strong local anomalies of As, Be, Ca, Cd, Cr, Cu, Hg, Ni, Pb, Sr, Ti and Zn near Pionki and Kozienice towns can be related to low efficiency of sewage treatment plants in metal removing.
Źródło:
Przegląd Geologiczny; 2007, 55, 1; 79-79
0033-2151
Pojawia się w:
Przegląd Geologiczny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Environmental stress in the northern Tethys during the Paleogene : a review of foraminiferal and geochemical records from the Polish Outer Carpathians
Autorzy:
Olszewska, B.
Szydło, A.
Powiązania:
https://bibliotekanauki.pl/articles/2060601.pdf
Data publikacji:
2017
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Outer Carpathians
Polska
Paleogene
foraminifera
geochemistry
Opis:
During the Paleogene, the area of the northern Tethys was controlled by a turbidity system stimulated by diastrophic and geodynamic processes. These factors contributed to the dispersion and rapid oxygenation of organic debris. Its accumulation was a consequence of stagnant bottom water conditions that periodically occurred in the basin. In these periods, intense decomposition intensified by hydrothermal and diagenetic processes was associated with oxygen consumption and the release of greenhouse gases, which led to hypoxia and acidification. These phenomena intensified by thermal and density stratification had a major impact on the structure, evolution and distribution of biota. Stress associated with rapidly changing conditions induced by sedimentary process and upwelling resulted in the dominance of forms that colonized most sediments (Glomospira, Ammodiscus, Recurvoides, Rzehakina) and surface waters (Guembelitria, Chiloguembelina, Globanomalina, Globigerina, Cassigerinella, Catapsydrax). At the time, foraminifera were limited to low-diversified eutrophic assemblages or were mainly replaced by siliceous phytoplankton (radiolarians and diatoms). Geochemical data confirm that environmental crises in the Paleogene basin took place under changing thermal conditions that reflect global events (KTBE, PTME, EEOC and TTE). Thermal stress favouring the formation of certain minerals or rocks occasionally occurred during the Paleocene to Eocene (siderite, phosphates) and dominated in the Early Oligocene (silica).
Źródło:
Geological Quarterly; 2017, 61, 3; 682--695
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Geochemical and foraminiferal records of environmental changes during the Zechstein Limestone (Lopingian) deposition in Northern Poland
Autorzy:
Peryt, M.
Peryt, D.
Powiązania:
https://bibliotekanauki.pl/articles/2058961.pdf
Data publikacji:
2012
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
geochemistry
Polska
carbon and oxygen isotopes
foraminifers
Zechstein Limestone
Opis:
The entire Zechstein Limestone section of the Zdrada IG 8 borehole (Northern Poland) is composed of oncoid packstone that is accompanied by stromatolites in the upper part of the unit. Deposition of the Zechstein Limestone occurred in persistently subtidal environments, above the storm wave base, in mostly dysoxic conditions, and thus these conditions did not differ essentially from those characteristic for the Kupferschiefer strata. The previous supposition of vadose diagenesis is not confirmed by the isotopic study of calcite that showed its clearly marine values (average d1318
Źródło:
Geological Quarterly; 2012, 56, 1; 187-198
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Geochemia i wykształcenie skał zubrowych górnego permu (cechsztyn) z obszaru Polski
Comparative geochemistry and development of the Upper Permian (Zechstein) zuber rocks from Poland
Autorzy:
Tomassi-Morawiec, Hanna
Wachowiak, Jacek
Czapowski, Grzegorz
Powiązania:
https://bibliotekanauki.pl/articles/2061456.pdf
Data publikacji:
2019
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
skały zubrowe
geochemia
cechsztyn
Polska
zuber rocks
geochemistry
Zechstein
Polska
Opis:
Praca prezentuje wyniki szczegółowych badań składu chemicznego skał zubrowych dwu głównych wydzieleń litostratygraficznych w cyklotemowej sukcesji osadów polskiego cechsztynu: zubra brunatnego (Na3t; cyklotem PZ3) i zubra czerwonego (Na4t; cyklotem PZ4) oraz innych cechsztyńskich ogniw i formacji zubrowych wyróżnionych na obszarze Polski. Skały te opróbowano w 2 wysadach solnych (Kłodawa i Mogilno) oraz w profilach 7 otworów wiertniczych. Utwory Na3t w wysadzie Kłodawa cechuje wyższy udział halitu w porównaniu ze skałami Na4t, które zawierają więcej materiału terygenicznego (materiał detrytyczny i substancja ilasta) co wyraża się większą średnią zawartością SiO2, Al2O3, Fe2O3 i K2O oraz wzbogaceniem w Mn, Rb, Zn i Zr w porównaniu z osadami Na3t. Skały Na3t w obu wysadach (Kłodawa i Mogilno) charakteryzują się wyższą średnią zawartością CaO, MgO i Sr w porównaniu z wydzieleniem Na4t, przede wszystkim dzięki wyższemu udziałowi węglanów Ca i Mg (głównie magnezytu) i podrzędnie kalcytu i dolomitu. Zawartość bromu w profilach Na3t w obu wysadach jest wyższa niż w osadach Na4t i jest charakterystyczna dla pierwotnych chlorków wytrącanych z morskiej solanki. Podobną zawartość bromu stwierdzono tylko w niektórych partiach sukcesji Na4t. W niektórych skałach profili Na4t zarejestrowany udział bromu <40 ppm sugeruje, że są one mieszaniną pierwotnych i wtórnych chlorków, powstałych wskutek recyklingu (rozpuszczanie i ponowne wytrącanie) wcześniej osadzonych morskich soli. Zmiany zawartości bromu w profilach opisanego wyżej wydzielenia Na4t oraz w profilach skał zubrowych subcyklotemów cyklotemu PZ4, opróbowanych w wybranych otworach wiertniczych z obszaru Niżu Polskiego wskazują, że środowisko depozycji zubrów ewoluowało od basenu morskiego (dolna część profilu Na4t i osady subcyklotemów PZ4a do PZ4b) do kontynentalnego jeziora solnego (górna część sukcesji Na4t i osady subcyklotemów PZ4c do PZ4e), w którym następowała kumulacja materiału terygenicznego i chlorków wytrąconych głównie z wtórnych, recyklingowych solanek. Udział takich składników jak: SiO2, Al2O3, MgO, K2O i Fe2O3, Rb, Zn i Zr, związanych głównie z obecnością substancji ilastej i materiału detrytycznego jest wyższy w przypadku skał typu zubra bezteksturalnego i warstwowanego w porównaniu z solami kamiennymi i zailonym, warstwowanymi i bezteksturalnymi. Obecność Sr i CaO, związanych z węglanami i siarczanami, jest częściej wyższa w solach kamiennych warstwowanych, gdzie pojawiają się laminy ilasto-anhydrytowe.
The paper presents results of detailed studies of chemical composition of zuber-like rocks of main two zuber lithostratigraphic units of the Polish Zechstein succession: the Brown Zuber (Na3t; PZ3 cyclothem) and the Red Zuber (Na4t; PZ4 cyclothem), as well as of other Zechstein zuber members and formations distinguished in Poland. These rocks were sampled from two salt domes (Kłodawa and Mogilno) and profiles of seven wells. Deposits of the Na3t unit in the Kłodawa dome have a higher content of halite compared with the Na4t unit. Deposits of the latter con - tain more terrigenous material (detrital and clay matter). They are characterized by higher average contents of SiO2 , Al2 O3 , Fe2 O3 and K2O and are enriched with Mn, Rb, Zn and Zr, compared with the Na3t succession. Rocks of the Na3t unit in both the Kłodawa and Mogilno domes are characterized by higher average contents of CaO, MgO and Sr than the deposits of the Na4t unit mainly due to their higher contents of Ca and Mg carbonates (with dominant magnesite) and, subordinately, of calcite and dolomite. Bromine content in the Na3t profiles of both domes is higher than in the Na4t deposits and it is characteristic for primary chlorides precipitated from marine brine. Such bromine concentration was found only in some parts of the Na4t succession. The bromine content <40 ppm, observed in some rocks of the Na4t profile, suggests that they are mixtures of primary and secondary chlorides, produced by recycling (dissolution and precipitation) of formerly accumulated marine salts. The bromine content changes, observed in the above-described Na4t unit profiles, as well as in the zuber profiles of the PZ4 subcyclo - thems, show that depositional environment of the zuber deposits evolved from a marine basin (in the lower part of the Na4t profile and in deposits of the PZ4a and PZ4b subcyclothems) to continental saline lakes (in the upper part of the Na4t succession and in deposits of the PZ4c to PZ4e subcyclothems), which trapped a terrigenous material an d chlorides precipitated mainly from secondary (recycled) brine s. The contents of such components as SiO2, Al2O3 , MgO, K2O, Fe2O3 , Rb, Zn and Zr, highly influenced by the content of clay matter and detrital material, are significantly higher in the structureless and layered zuber types, compared with the textural equivalents of clayey and rock salts. The contents of Sr and CaO, connected with carbonate and sulphate admixture, are commonly higher in the layered rock salts with frequent clay-anhydrite laminae.
Źródło:
Biuletyn Państwowego Instytutu Geologicznego; 2019, 477; 69--122
0867-6143
Pojawia się w:
Biuletyn Państwowego Instytutu Geologicznego
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Early Cretaceous intra-plate volcanism in the Pieniny Klippen Belt – a case study of the Velykyi Kamenets’/Vilkhivchyk (Ukraine) and Biała Woda (Poland) sections
Autorzy:
Oszczypko, N.
Salata, D.
Krobicki, M.
Powiązania:
https://bibliotekanauki.pl/articles/2060497.pdf
Data publikacji:
2012
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Polska
Ukraine
Pieniny Klippen Belt
Early Cretaceous
geochemistry
alkaline basalts
Opis:
The geological position and geochemistry of the basaltic sill and tuffs occurring within the Berriasian–?Albian pelagic limestones of the Czorsztyn Succession are described. The volcanic rock succession of the Velykyi (= Veliky) Kamenets’/Vilkhivchyk (= Vulkhovchik, Vulhovchik, Olkhivchyk) sites is related to intra-plate submarine volcanism, which took place at the southeastern termination of the Pieniny Klippen Belt. This volcanism was probably associated with the Early Cretaceous opening of the Magura/Fore-Magura basinal system, bounded by the Silesian/Marmarosh and Czorsztyn palaeoridges to the north and south respectively. The alkaline volcanic rocks from the Velykyi Kamenets’/Vilkhivchyk sites are geochemically similary to the basaltic block from Biała Woda (Małe Pieniny Mts., Poland), which is an olistolith a few metres across within the Jarmuta conglomerates (Maastrichtian/Paleocene). This basaltic block was eroded from the frontal part of the Czorsztyn Nappe and was deposited in the uppermost part of the Grajcarek Succession at the southeastern margin of the Magura Basin.
Źródło:
Geological Quarterly; 2012, 56, 4; 629--648
1641-7291
Pojawia się w:
Geological Quarterly
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Black "marble" in the Polish architecture - characteristics and possibility of its provenance determination: the case of the Dębnik limestone
Autorzy:
Marszałek, M.
Powiązania:
https://bibliotekanauki.pl/articles/184492.pdf
Data publikacji:
2014
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
black limestone
provenance
petrography
stable isotope geochemistry
deterioration
Polska
Belgium
Opis:
Black limestone, also known as black "marble", was widely used in the Polish small-scale architecture and art of the 17th and 18th centuries. Besides the Devonian limestone from Dębnik near Krakow, also popular were the Netherlandish (Wallonian), Devonian to Carboniferous limestones from the Meuse River and Schelde River valleys. This paper deals with the possibility of identifying the rocks imported to Poland. Macroscopic similarities between the Netherlandish rocks and some Dębnik limestones have been highlighted for the oldest Carmelite quarry in Dębnik, exploiting the best stones. The analyses include: optical microscopy, scanning electron microscopy with EDS, X-ray diffraction, X-ray fluorescence and isotope ratio mass spectrometry (13 C and 18 O stable isotopes). Carboniferous limestones from Netherlands can be identified within and distinguished from the Dębnik limestone in the macroscopic observations. Differences, depending on the varieties, are associated primarily with the presence of white calcite fragments of fossils, calcite veins intersecting the rock in all directions or hardness of the limestones. Deeply black Devonian limestones from Wallonia and Dębnik without macrofossils and calcite veins differ in microscopic observations considering their texture, type of microfossils and inventory of non-carbonate components. The characteristic graying and whitening of the black limestones has also been discussed as a possible feature of rock provenance.
Źródło:
Geology, Geophysics and Environment; 2014, 40, 2; 189-205
2299-8004
2353-0790
Pojawia się w:
Geology, Geophysics and Environment
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Provenance and diagenesis of siliciclastic and organic material in the Albian-Turonian sediments (Silesian Nappe, Lanckorona, Outer Carpathians, Poland): preliminary studies
Autorzy:
Wójcik-Tabol, P.
Ślączka, A.
Powiązania:
https://bibliotekanauki.pl/articles/191891.pdf
Data publikacji:
2009
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
organic and inorganic geochemistry
Albian-Turonian
Silesian Nappe
Outer Carpathians
Polska
Opis:
The provenance and diagenesis of the siliciclastic and hemipelagic sediments of three lithostratigraphic units: Lhoty Formation, Barnasiówka Radiolarian Shale Formation (BRSF) and Variegated Shales from Lancko- rona area, Polish Outer Carpathians, was approached by means of petrological and geochemical analysis of the representative samples. Data show that studied succession was mainly derived from two sources: 1. a dominant terrigenous fine-grained components have affinity with average upper continental crust (basing on mineral detritus, K2O/Rb ratio and Y/Ni vs. Cr/V ratios) and 2. biogenic siliceous material and macerals. Composition varies up section and accounts for changes in the detrital supply due to eustatic sea-evel changes. Organic petrology shows presence of organic detritus within the Lhoty Fm and dominance of marine-derived macerals in the BRSF. Chemical and petrological features imply a progressive deepening of the basin. The studied succession was diagenetically altered (e.g. coalification of bituminite, illitisation of smectite and pyritisation).
Źródło:
Annales Societatis Geologorum Poloniae; 2009, 79, No 1; 53-66
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Provenance and diagenesis of siliciclastic and organic material in the Albian-Turonian sediments (Silesian Nappe, Lanckorona, Outer Carpathians, Poland): preliminary studies
Autorzy:
Wójcik-Tabol, P.
Ślączka, A.
Powiązania:
https://bibliotekanauki.pl/articles/191389.pdf
Data publikacji:
2009
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
organic and inorganic geochemistry
Albian-Turonian
Silesian Nappe
Outer Carpathians
Polska
Opis:
The provenance and diagenesis of the siliciclastic and hemipelagic sediments of three lithostratigraphic units: Lhoty Formation, Barnasiówka Radiolarian Shale Formation (BRSF) and Variegated Shales from Lancko- rona area, Polish Outer Carpathians, was approached by means of petrological and geochemical analysis of the representative samples. Data show that studied succession was mainly derived from two sources: 1. a dominant terrigenous fine-grained components have affinity with average upper continental crust (basing on mineral detritus, K2O/Rb ratio and Y/Ni vs. Cr/V ratios) and 2. biogenic siliceous material and macerals. Composition varies up section and accounts for changes in the detrital supply due to eustatic sea-level changes. Organic petrology shows presence of organic detritus within the Lhoty Fm and dominance of marine-derived macerals in the BRSF. Chemical and petrological features imply a progressive deepening of the basin. The studied succession was diagenetically altered (e.g. coalification of bituminite, illitisation of smectite and pyritisation).
Źródło:
Annales Societatis Geologorum Poloniae; 2009, 79, No 2; 53-66
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Geochemistry of surface sediments of a coastal Lake Sarbsko (northern Poland)
Autorzy:
Woszczyk, Michał
Cieśliński, Roman
Spychalski, Waldemar
Powiązania:
https://bibliotekanauki.pl/articles/2026076.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
coastal lake
lake sediment geochemistry
Gardno-Łeba Coastal Plain
southern Baltic
Polska
Opis:
The main goal of the pre sented re search was to in ves ti gate spa tial dis tri bu tion of sur face sed i ments and to rec og nize re la tion ships be tween chem i cal com po si tion of wa ter and sed i ments in a coastal Lake Sarbsko (north ern Po land). The Lake Sarbsko is a fresh wa ter ba sin. The wa ter col umn is well ox y gen ated and wa ters ex hibit only mi nor spa tial vari - abil ity of chem i cal com po si tion in di cat ing rapid and good mix ing. Sur face sed i ments of Lake Sarbsko are strongly di - ver si fied with re spect to chem i cal com po si tion. The sed i ments of Lake Sarbsko are char ac ter ized by el e vated con tent of terrigenous sil ica in di cat ing en hanced in put of clastic ma te rial from the wa ter shed and/or in creased dy nam ics of the lake wa ters. More over, SiO2ter is strongly neg a - tively cor re lated with SiO2biog, or ganic mat ter and el e ment con tents, which ar gues for di lut ing ef fect of the for mer to - wards authigenic com po nents of sed i ments. Ba si cally, terrigenous sil ica (quartz) con tent is high est in the lake shores and de clines to wards the lake cen ter. Biogenic sil ica, or ganic mat ter and most of el e ments dis play re versed ten dency. CaCO3 was en coun tered in three iso lated ar eas, where it co-oc curs with FeS. It is an tic i pated that pre cip i ta tion of cal - cite in Lake Sarbsko re sulted from postdepositional pro cesses. Spa tial dis tri bu tion of Fe, Mn, Ca, Mg, Na and K in Lake Sarbsko is also gov erned by their geo chem i cal af fin i ties to or ganic mat ter (Fe), Fe/Mn ox ides (Fe, Mn), sulphides (Fe), clay min er als (Na, K, Mg, Mn) and car bon ates (Ca, Mn).
Źródło:
Studia Quaternaria; 2009, 26; 41-53
1641-5558
2300-0384
Pojawia się w:
Studia Quaternaria
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Environmental changes around the Cenomanian-Turonian boundary in a marginal part of the Outer Carpathian Basin expressed by microfacies, microfossils and chemical records in the Skole Nappe (Poland)
Zmiany w głębokowodnym środowisku brzeżnej części basenu Karpat Zewnętrznych wokół granicy Cenomanu i Turonu wyrażone w zapisie mikrofacji, zespołach mikroskamieniałości i chemizmie utworów w Płaszczowinie Skolskiej
Autorzy:
Bąk, K.
Powiązania:
https://bibliotekanauki.pl/articles/191678.pdf
Data publikacji:
2007
Wydawca:
Polskie Towarzystwo Geologiczne
Tematy:
Cenomanian-Turonian boundary event
microfacies
benthic foraminifers
bulk geochemistry
Outer Carpathians
Polska
Opis:
Lithology, microfacies, benthic foraminiferal and bulk chemical analyses of the Spława section in the Skole Nappe, Outer Carpathians (Poland) reflect environmental changes across the Cenomanian-Turonian transi- tion. Biogenic-rich-turbidite sedimentation preceded the organic-rich sedimentation in the Skole Basin, termina- ting in the latest Cenomanian in response to progressive eustatic sea-level rise and to expansion of an oxygen minimum zone. The uppermost Cenomanian black, laminated, organic-rich shale series records the oceanic anoxic event (OAE-2). The benthos-free black non-calcareous shales exhibiting positive excursions of chemical redox indexes are indicative of bottom-water anoxia, interrupted by periods of suboxic conditions with sedimentation of hemipelagic green shales with poor agglutinated foraminiferal assemblages. An extremely low sedimentation rate or even a hiatus and an increase in deep-water circulation causing basin oxygenation resulted in precipitation of a ferromanganese layers and siliceous-manganiferrous variegated shales, as documented by low values of chemical redox indices. However, the lack of benthos and bioturbation, and low values of the Ce/La ratio in the subsequent succession of variegated shales (dominated by green shales) indicate a return to stressed conditions at basin floor with sluggish bottom water circulation, which occasionally resulted in sea floor anoxia with deposition of organic-rich shales. The long-termed well-oxygenated conditions at the basin floor appeared in the Early Turo- nian, as documented by diversified benthic foraminiferal assemblages. The frequency of radiolarian-rich layers and Ba/Al and Ba/Sc ratios increase up-section, reflecting an increase in primary productivity, induced by upwelling circulation.
Źródło:
Annales Societatis Geologorum Poloniae; 2007, 77, No 1; 39-67
0208-9068
Pojawia się w:
Annales Societatis Geologorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nanostructural and geochemical features of the Jurassic isocrinid columnal ossicles
Autorzy:
Stolarski, J
Gorzelak, P.
Mazur, M.
Marrocchi, Y.
Meibom, A.
Powiązania:
https://bibliotekanauki.pl/articles/22326.pdf
Data publikacji:
2009
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
isocrinid columnal ossicle
geochemistry
Polska
Gnaszyn Dolny
ossiculum zob.ossicle
paleontology
Echinodermata
Crinoidea
Jurassic
ossicle
calcite
nanostructure
Opis:
Calcite isocrinid ossicles from the Middle Jurassic (Bathonian) clays in Gnaszyn (central Poland) show perfectly preserved micro− and nanostructural details typical of diagenetically unaltered echinoderm skeleton. Stereom pores are filled with ferroan calcite cements that sealed off the skeleton from diagenetic fluids and prevented structural and geochemical alteration. In contrast with high−Mg calcite skeleton of modern, tropical echinoderms, the fossil crinoid ossicles from Gnaszyn contain only 5.0–5.3 mole% of MgCO₃. This low Mg content can be a result of either a low temperature environment (ca. 10℃) and/or low Mg/Ca seawater ratio. Both conditions have been proposed for the Middle Jurassic marine environment. Occurrence of Mg−enriched central region of stereom bars of Jurassic columnal ossicle of Chariocrinus andreae is consistent with the concept of magnesium ions involvement in earliest growth phases of calcium carbonate biominerals.
Źródło:
Acta Palaeontologica Polonica; 2009, 54, 1; 69-75
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The weathering-modified iridium record of a new Cretaceous–Palaeogene site at Lechowka near Chelm, SE Poland, and its palaeobiologic implications
Autorzy:
Racki, G.
Michalski, M.
Koeberl, C.
Harasimiuk, M.
Powiązania:
https://bibliotekanauki.pl/articles/20009.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
Cretaceous
geochemical anomaly
Lechowka n.Chelm
Paleogene
Polska
anomaly
biostratigraphy
extinction
geochemistry
geological setting
iridium
lithology
paleobiology
paleontology
weathering-modified iridium
Opis:
In the light of integrated biostratigraphic and geochemical data, a complete shallow−marine succession across the Cretaceous–Palaeogene (K–Pg) boundary, with the critical boundary clay coupled with a burrowed siliceous chalk (“opoka” in Polish geological literature), possibly equivalent of the basal Danian Cerithium Limestone in Denmark, has been discovered at Lechówka near Chełm, SE Poland. An extraterrestrial signature marking the K–Pg boundary is confirmed by anomalously high amounts of iridium (up to 9.8 ppb) and other siderophile elements (especially Au and Ni), as well as by an elevated Ir/Au ratio consistent with a chondrite meteoritic composition. The major positive iridium spike surprisingly occurs in Maastrichtian marls, 10 cm below the boundary clay interval, which can be explained by diagenetic mobilisation and re−concentration of the impact−derived components. Thus, intensively infiltrating, humic acid−rich ground waters during the long−lasting Palaeogene weathering in tropical humid regimes were probably responsible not only for the large−scale decalcification of the Lechówka section, but also for both downward displaced position of the iridium enrichment, a dispersed profile of this anomaly and its significantly lessened value, but still approaching an increase by a factor of 100. This modified record of the K–Pg boundary event points to a careful reconsideration of the iridium anomaly as a trustworthy marker for studying the extinction patterns across the K–Pg boundary, as supported by the recent data from New Jersey, USA.
Źródło:
Acta Palaeontologica Polonica; 2011, 56, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
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