Architectural analysis of a Triassic fluvial system: the Sherwood Sandstone of the East Midlands Shelf, UK

The Sherwood Sandstone Group of the northeast UK (East Midlands Shelf) has hitherto never been studied in detail to ascertain its palaeoenvironment of deposition, largely because it is poorly exposed. As such, this paper aims to provide the first modern sedimentological interpretation of the Sherwood Sandstone in the east of England based on a field outcrop at the disused quarry at Styrrup. This is in stark contrast to the western parts of England where the Sherwood Sandstone is well exposed and offshore in the North Sea Basin where it is represented by a substantial library of core material where it is also relatively well understood. The outcrop at Styrrup Quarry allows contrasts to be made with the style and expression of the Sherwood Sandstone between eastern and western England. Specifically, this highlights differences around the variation in fluvial discharge (between lowstand and highstand) and the absence of aeolian facies types. It is interpreted that these differences relate to discharge variations between ephemeral and perennial systems with a perennial model proposed for Styrrup Quarry. This model draws upon inferences of additional water input from more local areas, likely topographic uplands of the London–Brabant and Pennine Highs which supplement the primary source of the Variscan Mountains in France with additional water and sediment.