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Central European Geology
Authors: Zsófia Pálos, István János Kovács, Dávid Karátson, Tamás Biró, Judit Sándorné Kovács, Éva Bertalan, Anikó Besnyi, György Falus, Tamás Fancsik, Martina Tribus, László Előd Aradi, Csaba Szabó and Viktor Wesztergom

lava dome ( Karátson 2007 ). Sample no. 6 from Bajdázó quarry is also (probably root) the part of a garnet-bearing dacitelava dome. Sample nos. 7 and 8 are pyroclastic rocks. Sample no. 7 of Királyrét is a biotite-dacitic clast of a garnet

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Acta Geologica Hungarica
Authors: Réka Lukács, György Czuppon, Szabolcs Harangi, Csaba Szabó, Theodor Ntaflos and Friedrich Koller

, D. Karátson, D. Sarocchi, L. Valentini 1995: Early Miocene pyroclastic rocks of the Bükkalja Ignimbrite Field (North Hungary) - A preliminary stratigraphic report. - In: H. Downes, O. Vaselli (Eds): Neogene and related magmatism in the Carpatho

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–dacites ( Szemerédi et al. 2020 ). Moreover, felsic pyroclastic rocks in SE Hungary proved to be slightly younger than other Permian volcanic rocks of the Tisza MU ( Szemerédi et al. 2020 ). The aim of this study is to provide a detailed petrographic description of

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–dacites ( Szemerédi et al. 2020 ). Moreover, felsic pyroclastic rocks in SE Hungary proved to be slightly younger than other Permian volcanic rocks of the Tisza MU ( Szemerédi et al. 2020 ). The aim of this study is to provide a detailed petrographic description of

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Permo-Triassic rift-related magmatism in the Dinarides produced an intrusive gabbro-diorite-syenite-granite formation and an extrusive basalt-andesite-dacite formation with abundant pyroclastic rocks. They are spatially and genetically related to Late Permian to Norian rift-related sedimentary formations of the Adriatic-Dinaridic carbonate platform (ADCP). The volcanic and pyroclastic rocks are interlayered with fossiliferous sediments that range between the Late Permian and Middle Norian; the plutonic rocks, which are intrusive into Late Paleozoic and Scythian-Anisian sediments, have radiometric ages ranging between 262 and 212 Ma. Based on major and trace element contents, rocks of the Permo-Triassic magmatic association originated by fractional crystallization from primitive alkalic basalt to olivine tholeiite melts. Volcanic rocks were affected by strong ocean-hydrothermal metamorphism. Initial 87Sr/86Sr ratio of 0.703 and d18O of 5.6‰ of the most primitive rocks indicate an upper mantle origin. Most initial 87Sr/86Sr ratios range between 0.704-0.707, indicating a slight degree of crustal contamination. The Permo-Triassic igneous rocks of the Dinarides represent a specific and autonomous paleorift-related association, which cannot be correlated with the magmatic associations either from recent oceans or with alkali rocks from the Cenozoic African rift and Permian Oslo graben.

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Abstract  

The preliminary results of indoor radon concentration measurements taken in some of Mexico City’s colonial churches and convents are presented. Measurements were taken in the churches of Santa Catarina, La Conchita, San Juan Bautista, San Antonio Panzacola, San Diego and San Mateo and the church and convent complex of El Carmen. These structures are all located in Coyoacan, a borough of Mexico City. Indoor radon concentrations in churches and convents constructed in the 17th and 18th centuries are interesting for several reasons. Most of these buildings were built using the stones of ancient Mexican pyramids, mainly blocks of basalt and volcanic pyroclastic rocks, and possess walls between 40 cm and 70 cm thick and naves with large volumes of air and relative low ventilation. The churches are public places with people most of the time. The indoor radon concentrations were measured using nuclear track detectors consisting of a closed-end cup containing CR-39 Lantrack® polymer as detector material. The measurements were taken over four periods of three consecutive months. The results show indoor radon concentrations of between 82 and 165 Bq·m−3, below to the United States Environmental Protection Agency (USEPA) indoor radon action level for workplaces. Using these results, the radiological risks were calculated and found to be negligible.

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. Ravaszné Baranyai, Kad. Balogh, E. Árva-Soós 1979: K/Ar dating of Miocene pyroclastic rocks in Hungary. - Annales Géologiques des Pays Hellenéniques. Hors Série., 2, pp. 491 - 501 . K/Ar dating of Miocene pyroclastic rocks in

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R. Lukács 2005 Correlation of silicic pyroclastic rocks in the Northern Pannonian Basin, Eastern-Central Europe: a geochemical approach Journal of Volcanology and Geothermal

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L. Valentini 1995 Early Miocene pyroclastic rocks of the Bükkalja Ignimbrite Field (North Hungary) — A preliminary stratigraphic report Acta Vulcanologica

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P.R.D. Mason R. Lukács 2005 Correlation and petrogenesis of silicic pyroclastic rocks in the Northern Pannonian Basin, Eastern-Central Europe: In

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