“Calcispheres” as a source of lime mud and peloids – evidence from the early Middle Devonian of the Prague Basin, the Czech Republic


Authors: Berkyová S, Munnecke A

Published in: Bulletin of Geosciences, volume 85, issue 4; pages: 585 - 602; Received 20 July 2010; Accepted in revised form 27 October 2010; Online 13 December 2010

Keywords: calcispheres, peloids, micritization, lime mud, Prague Basin, Devonian,

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Several types of peloids are present in the Lower and Middle Devonian limestones of the Prague Basin (uppermost part of the Třebotov Limestone of the Daleje-Třebotov Formation and Choteč Formation, uppermost Emsian–Eifelian) and are interpreted as being of calcispheral, echinoderm, and/or calcimicrobial origin. Possible mechanisms of peloid formation, the mode of life of calcispheres and their role in the accumulation of Paleozoic lime mud are discussed. Mass occurrences of peloids and calcispheres are characteristic features of the Choteč Formation (Eifelian, costatuskockelianus conodont zones). It is concluded that specific environmental conditions, such as a higher nutrient load, existed during the sedimentation of this unit, probably in response to the Basal Choteč event.


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