Five lithofacies are defined on petrographic and field data from a single limestone unit in a deltaic clastic/carbonate sequence of late Namurian-early Westphalian age. These are: (1) Donezella bafflestone, (2) bioclastic wackestone, (3) bioclastic packstone, (4) oncolitic, whole fossil wackestone, and (5) sparsely fossiliferous wackestone facies. Sedimentation took place during a marine transgression onto a shallow, low-energy shelf connected to an extensive carbonate platform. Facies variations within the limestone appear to be related to depth and energy changes and proximity to areas of clastic deposition. These changes may have been controlled by tectonic events in the hinterland and changes in the rate of basin subsidence. The problematic tubular micro-organism Donezella colonised the sea floor during periods of maximum transgression, forming small mounds (the Donezella bafflestone facies).
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