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.