Perunica microplate: relation to Ukrainian Shield, mid-Bohemian rift, and hypothetic large-scale overthrusts in central Bohemia


Authors: Havlíček V

Published in: Bulletin of Geosciences, volume 74, issue 1; pages: 75 - 86;

Keywords: Perunica, climatic zones, rifts in central Bohemia, hypothetic large-scale nappes,

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Although the basic pattern of the Lower Palaeozoic palaeogeography, benthic communities of invertebrates, origin of sedimentary basins in central Bohemia, and tectonic processes were summed up by Chlupáč at al. (1998), some interesting problems remained to be discussed. The first one concerns the revision of climatic zones of the Lower Palaeozoic successions in Perunica and their comparison with those of the Brunovistulicum (western component of the Ukrainian Shield) to show that no extreme distances in the meridian direction existed between them. Secondly, the Central Bohemian suture, separating the units of Bohemicum (including the Teplá-Barrandian Block) and Moldanubicum, functioned in the Lower Palaeozoic as a supposed mid-Bohemian rift (Havlíček 1995); it was the most logical sea-way of migration of planktic and benthic elements into central Bohemia. Further, the axial part of the Prague Basin presents another rift paralleling the main mid-Bohemian rift zone, but much less tectonically disturbed and bearing unmetamorphosed Lower Palaeozoic successions famous for their richly diversified associations of various animal groups. In the end, the last considerations concern the existence of a thick rock complex forming probable large-scale nappes, which protected even the latest Devonian formations against their total destruction during the long periods, when central Bohemia became a permanently rising dry land.