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N. Yu. Matushkin D. V. Metelkin V. A. Vernikovsky A. V. Travin A. I. Zhdanova 《Doklady Earth Sciences》2016,467(1):219-223
The paper presents the first data on the geology of a series of mafic dikes emplaced in the volcanogenic sedimentary sequence composing the structure of Jeannette Island. We show that the island hosts two generations of dikes consisting of fine-grained dolerites. Both magmatic stages were followed by fold deformations. The youngest and weakly deformed dikes are none the less chloritized and serpentinized. However, we were able to obtain the first ever precise geochronological 40Ar/39Ar data for them. According to this analysis, the emplacement age of the intrusive complex of Jeannette Island is close to the Ediacaran (553.6 ± 10.3 Ma). The ages of several superimposed tectonothermal events were determined: Middle Ordovician (463.3 ± 11.7 Ma), Late Silurian (425.3 ± 8.7 Ma), Late Devonian (360.7 ± 8.3 Ma) and Early Carboniferous (341.3 ± 6.8 Ma). 相似文献
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A. I. Zhdanova D. V. Metelkin V. A. Vernikovsky N. Yu. Matushkin 《Doklady Earth Sciences》2016,468(2):580-583
The first paleomagnetic data on dolerite dikes from the volcanogenic–sedimentary section of Jeannette Island (De Long Archipelago, New Siberian Islands) are discussed. The petromagnetic data and results of the baked contact and fold tests are used to substantiate the nature of the characteristic magnetization component, which in combination with the 40Ar/39Ar dates implies its likely Late Precambrian–Early Paleozoic age. The calculated paleomagnetic pole makes it possible to extend the trajectory of the apparent polar movement for the New Siberian Islands block and confirms the assumption that this structural element of the Arctic shelf evolved as a terrane. Two variants of paleotectonic interpretation of the obtained data and their consistency with the available data on the geology and tectonics of the New Siberian Islands are considered. 相似文献
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A. I. Chernova D. V. Metelkin N. Yu. Matushkin V. A. Vernikovsky A. V. Travin 《Doklady Earth Sciences》2017,475(2):849-853
The paper presents results of geochronological and paleomagnetic studies of the volcanogenicsedimentary sequence of Henrietta Island in the East Siberian Sea. Our 40Ar/39Ar investigations confirm existing ideas that the bottom part of the section formed in the Ediacaran (~565 Ma) and that the basalts in the top of the section formed before the middle Cambrian (~520 Ma). Calculated paleomagnetic data confirm that during the rocks formation the territory of present-day Henrietta Island was located close to the 20° latitude, which lets us adjust some information published earlier on the age and natural remanent magnetization of the dolerite dikes of the nearby Jeannette Island. The new data also let us propose that a regional tectonothermal event, probably caused by accretion-related processes, took place at the beginning of the Ordovician. 相似文献
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D. V. Metelkin A. I. Chernova V. A. Vernikovsky N. Yu. Matushkin 《Doklady Earth Sciences》2017,477(1):1277-1281
The New Siberian Islands archipelago is one of the few research objects accessible for direct study on the eastern Arctic shelf. There are several models that have different interpretations of the Paleozoic tectonic history and the structural affinity of the New Siberian Islands terrane. Some infer a direct relationship with the passive continental margin of the Siberian paleocontinent. Others connect it with the marginal basins of Baltica and Laurentia, or the Chukotka-Alaska microplate. Our paleomagnetic investigation led us to create an apparent polar wander path for the early Paleozoic interval of geological history. Based on it we can conclude that the New Siberian Islands terrane could not have been a part of these continental plates. This study considers the possible tectonic scenarios of the Paleozoic history of the Earth, presents and discusses the corresponding global reconstructions describing the paleogeography and probable mutual kinematics of the terranes of the Eastern Arctic. 相似文献
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A.E. Vernikovskaya V.A. Vernikovsky N.Yu. Matushkin O.P. Polyansky A.V. Travin 《Russian Geology and Geophysics》2009,50(5):438-452
Results of complex geological, petrological, geochemical, and isotope-geochronological studies of Neoproterozoic postcollisional A-type granites of the Glushikha complex, Yenisei Ridge, are presented, as well as results of mathematical modeling. The localization, sizes, and depths of formation of magmatic bodies and the physicochemical conditions of the formation of granite intrusions and their magmatic sources are considered. The research is focused on the modeling of the thermal history of the formation and subsequent cooling of granites in the collision orogen. The modeling of heat transfer during the acid-magma intrusion was performed by the example of the Lendakha and Glushikha leucogranite plutons. With the combined methods of the modeling of heat transfer and the behavior of K/Ar isotopic system, the models for leucogranite pluton cooling have been verified for the first time. The time of formation and cooling of granite bodies is estimated, and a generalized geodynamic model for the formation of the Glushikha postcollisional A-type leucogranites is proposed. 相似文献
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Metelkin D. V. Chernova A. I. Matushkin N. Yu. Vernikovsky V. A. 《Doklady Earth Sciences》2020,495(1):803-807
Doklady Earth Sciences - This work presents finalized results of our paleomagnetic study of Paleozoic rocks of Henrietta, Jeannette and Bennett islands and their implications for tectonic... 相似文献
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A. E. Vernikovskaya V. M. Datsenko V. A. Vernikovsky N. Yu. Matushkin Yu. M. Laevsky I. V. Romanova A. V. Travin K. V. Voronin E. N. Lepekhina 《Doklady Earth Sciences》2013,448(2):161-167
Neoproterozoic carbonatites and related igneous rocks, including A-type granites in the Tatarka-Ishimba suture zone of the Yenisey Ridge are confined to a horst-anticlinal structure that was formed in a transpression setting during the oblique collision between the Central Angara terrane and the Siberian craton. The carbonatites, associating mafic (including alkaline) dikes as well as the Srednetatarka nepheline syenites are the oldest igneous formations of the Tatarka active continental margin complex. Geochronological data indicate that magmatic evolution continued in the studied anticline for nearly 100 m.y. On the earliest stage carbonatites were formed and on the last stage — the emplacement of mantle-crustal A-type Tatarka granites took place. According to new U/Pb zircon studies, the earliest rocks in the Tatarka pluton are A-type leucogranites aged 646 ± 8 Ma. The younger 40Ar/39Ar ages of carbonatites obtained for phlogopites (647 ± 7 and 629 ± 6 Ma) are related to the last tectonic events in the studied region of the Tatarka-Ishimba suture zone, which are coeval with the formation of the A-type granitoids (646–629 Ma). 相似文献
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