Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "U-Pb geochronology" wg kryterium: Temat

  Lista filtrów
Wyrównaj
    Wyświetlanie 1-2 z 2
    Tytuł:
    Age constraints on the Pre-Variscan and Variscan thermal events in the Kamieniec Ząbkowicki Metamorphic belt (the Fore-Sudetic Block, SW Poland)
    Autorzy:
    Jastrzębski, Mirosław
    Żelaźniewicz, Andrzej
    Budzyń, Bartosz
    Sláma, Jiří
    Konečny, Patrik
    Powiązania:
    https://bibliotekanauki.pl/articles/1836361.pdf
    Data publikacji:
    2020
    Wydawca:
    Polskie Towarzystwo Geologiczne
    Tematy:
    U-Pb geochronology
    LA-ICP-MS dating
    U-Th-total Pb geochronology
    EPMA dating
    microplates of the Bohemian Massif
    Kamieniec Ząbkowicki Metamorphic Belt
    Variscan metamorphism
    Opis:
    The Kamieniec Ząbkowicki Metamorphic Belt (KZMB) is a narrow zone of mainly mica schists, subordinate acid metavolcanics and scarce eclogites, sandwiched between Brunovistulia and the northern tip of the Teplá-Barrandia microplates. Locally occurring high-pressure relics indicate subduction of the metasedimentary succession of the KZMB, the origin and provenance of which remain unclear. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) investigations of detrital zircons show that the metapelites represent an Ediacaran-Cambrian sedimentary basin, with a maximum depositional age of 561±9 Ma. This basin was filled with detritus from a source or sources, composed of rocks containing zircons that are mainly Cryogenian-Ediacaran and Palaeoproterozoic in age. No younger component was found in the zircon population studied. The isotopic U-Pb LA-ICP-MS and chemical U-Th-total Pb electron probe microanalysis (EPMA) monazite geochronology data indicate an important regional tectono-metamorphic event at ca. 330 Ma. Though these data do not permit determination of the peak pressure from the peak temperature stages, the event was part of a complex collision of the Saxothuringian plate with Brunovistulia.
    Źródło:
    Annales Societatis Geologorum Poloniae; 2020, 90, 1; 27-49
    0208-9068
    Pojawia się w:
    Annales Societatis Geologorum Poloniae
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Early Devonian sinistral shearing recorded by retrograde monazite-(Ce) in Oscar II Land, Svalbard
    Autorzy:
    Ziemniak, Grzegorz
    Manecki, Maciej
    Jeanneret, Pauline
    Walczak, Katarzyna
    Kośmińska, Karolina
    Powiązania:
    https://bibliotekanauki.pl/articles/2202387.pdf
    Data publikacji:
    2022
    Wydawca:
    Polskie Towarzystwo Mineralogiczne
    Tematy:
    Retrograde monazite-(Ce)
    Svalbard’s Southwestern Basement Province
    U-Th-total Pb geochronology
    Müllerneset Formation
    Caledonian orogeny
    Opis:
    The Southwestern Basement Province of Svalbard extends northward from Sørkapp Land in the south to Oscar II Land. In the north, the Müllerneset Formation characterized by polymetamorphosed Proterozoic sedimentary rocks crops out. In this study we used an integrated tectonic and petrochronological approach to gain an insight into the structural and metamorphic evolution of the unit and surrounding basement. The Müllerneset Formation consists of two separate tectonic blocks. NNW-SSE trending retrograde foliation is associated with mineral and stretching lineation and kinematic indicators consistent with left-lateral to oblique sinistral shearing in the western block. The eastern block is characterized by the opposite sense of shear that was overturned during the Eurekan event as evidenced by unconformably overlaying Carboniferous sedimentary rocks. Conventional geothermobarometry yields the prograde peak pressure metamorphic conditions of 6.6 - 7.1 kbar at 480 - 520°C followed by peak temperature at 5.1 - 5.9 kbar and 530 - 560°C. Subsequent retrograde greenschist facies overprint is related to left-lateral NNW-SSE trending shearing. Tiny monazite occurs within foliation or overgrows allanite-(Ce), thus is interpreted as growth along a retrograde path. Th-U-total Pb dating of monazite-(Ce) provided an early Caledonian age (ca. 450 Ma) and younger population of ca. 410 ± 8 Ma. This age is consistent with previously reported 40Ar/39Ar cooling ages (410 ± 2 Ma) of muscovite supporting a retrograde growth of monazite. Petrochronological evidence combined with structural observations suggests that the Müllerneset Formation has been tectonically exhumed in the Early Devonian due to the NNW-SSE trending left-lateral shearing. Coeval folding and thrusting in the remaining basement of Oscar II Land to the east indicate a transpressional regime of the deformation in the Early Devonian. Similarly oriented contemporaneous tectonic zones within the Southwestern Basement Province of Svalbard may account for the same set of shear zones dispersing the Ordovician subduction complexes along western Spitsbergen.
    Źródło:
    Mineralogia; 2022, 53, 1; 82--108
    1899-8291
    1899-8526
    Pojawia się w:
    Mineralogia
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
      Wyświetlanie 1-2 z 2

      Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies