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IMPF: 00.66A synthesis of the upper Moscovian sedimentotogical and palaeontological record of terrestrial habitats across the Variscan foreland and adjacent intramontane basins (an area which is referred to here as Variscan Euramerica) suggests a contraction and progressive westward shift of the coal swamps. These changes can be correlated with pulses of tectonic activity (tectonic phases) resulting from the northwards migration of the Variscan Front. This tectonic activity caused disruption to the landscapes and drainage patterns where the coat swamps were growing, which became less suitable to growth of the dominant plants of the swamps, the arborescent lycopsids. They were progressively replaced by vegetation dominated by marattialean ferns, which through a combination of slower growth and larger canopies resulted in less evapo-transpiration. This in turn caused localised reductions in rainfall, which further affected the ability of the lycopsids to dominate the swamp vegetation. These changes were initially localised and where the coat swamps were able to survive the lycopsids and pteridosperms show little change in either species diversity or biogeography, indicating that at this time there was minimal regional-scale climate change taking place. By Asturian times, however, the process had accelerated and the swamps in Variscan Euramerica became progressively replaced by predominantly conifer and cordaite vegetation that favoured much drier substrates. Except in localised pockets in intramontane basins of the Variscan Mountains, the last development of coat swamps in Variscan Euramerica was of early Cantabrian age. Further west, lycopsid-dominated coal swamps persisted for a little longer. The last remnants of the lycopsid-dominated coal swamps in the Illinois Basin disappeared probably by middle-late Cantabrian times, as the cycle of contracting wetlands and regional reductions in rainfall generated its own momentum, and no longer needed the impetus of tectonic instability. This tectonically-driven decline in the Euramerican coal swamps was probably responsible for an annual increase in atmospheric CO2 of c. 0.37 ppm, and may have been implicated in the marked increase in global temperatures near the Moscovian - Kasimovian boundary, and the onset of the Late Pennsylvanian interglacial.Peer reviewe

The coal-bearing succession of the Upper Silesia Coal Basin consists of deposits filling a flexural foredeep basin. Accumulation initially compensated for regional and differentiated subsidence, after which the general depositional surface remained nearly flat. The deposition of the coal-bearing succession started at the end of Mississippian times (Pendleian Subage) and continued with hiatuses through almost the whole of Pennsylvanian times, and stopped in the Westphalian D Subage. The up to 8500 m thick coal-bearing succession traditionally has been divided into four main units called 'Series', and all of them are subdivided into subsidiary units known as 'Beds'. The occurrence of the intervals containing marine faunas within the lower 'Paralic' part of the coal-bearing succession resulted from eustatic ingressions. The higher 'Limnic' part of the succession was laid down in fluvial systems, while the lower part was formed mostly in a fluvial and, to a lesser extent, complex coastal system. Sedimentation of the coal-bearing succession was controlled by both autogenic and allogenic factors.