Intrusive rocks in the Barrandian Proterozoic and their chemical composition

 

David Dolejš

Geoscience Research Reports 41, 2008 (GRR for 2007), pages 151–155

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Abstract

Intrusive clusters, stocks and dyke swarms emplaced in the Neoproterozoic basement of the northwestern Barrandian reveal four tectonomagmatic events during the Paleozoic era: (1) tholeiitic gabbros and norites of the Mladotice complex, which are similar to Kdyně, Poběžovice and Bechlín bodies of Cambrian age; (2) medium- to high-K calc-alkaline quartz diorites to granodiorites of the Kožlany intrusive zone, which are geochemically comparable to the 2nd extrusive phase of the Křivoklát-Rokycany volcanic belt; (3) mafic stocks and dyke swarms ranging from subalkaline to alkaline types with appinitic and lamprophyric textures, whose chemical composition resembles that of Ordovician or Silurian volcanics of the Barrandian; (4) calc-alkaline quartz diorite to granodiorite porphyries, which appear to be related to the Čistá granodiorite pluton. Intermediate extrusives and intrusives are often accompanied by spatially restricted occurrences of granite, aplite, rhyolite or spessartite dykes.