A fabric and petrologic study of the Pleasantview Sandstone

The Pleasantview sandstone is a typical Pennsylvanian cyclothem sandstone in western Illinois exhibiting both channel and non-channel phases. In order to describe the sandstone and to interpret the sediment transport direction and the environmental conditions existing at the time of deposition, an investigation was made of the texture, composition, depositional structure, cross-bedding, and dimensional fabric. Results of this study indicate that the sandstone is a subgraywacke which was deposited in a north and northwest direction. It is concluded that the process which cut the Pleasantview channel was to a large degree independent of the processes which later filled the channel with sediment. No conclusive evidence could be found for the exact nature of the processes operating at the time of channel cutting and filling. However, it is suggested that the environmental conditions of the Pleasantview most closely resemble those conditions existing at present in the Dutch Wadden Sea.