Provenance response to evolving palaeogeography recorded by Carboniferous sandstones in the northern Pennine Basin, UK

Abstract

On the basis of a combination of heavy mineral data, provenance-sensitive heavy mineral indices, garnet major element chemistry, rutile trace element chemistry and zircon U–Pb geochronology, six major changes in sandstone provenance during Carboniferous deposition in the northern Pennine Basin, UK, have been recognised. These changes are a manifestation of both tectonic and climatic factors. The earliest Tournaisian sediment was supplied from the local Southern Uplands High, but the increasingly humid climate led to the establishment of the Pennine River system, which introduced northerly-derived sediment from farther afield in the mid Tournaisian. This system was operative until the mid Bolsovian, but shows stratigraphic variations due to changes in input from different parts of the Pennine River hinterland (East Greenland, northern Scotland, western Norway). These variations are believed to be at least partly related to tectonism, since the maximum supply from high-grade metamorphic sources in East Greenland in the Namurian was concurrent with a tectonically-driven change in drainage direction in this part of the northern sourcelands. In addition, at the base of the Visean, there was a temporary influx of mature sediment coincident with a climatically-driven regression and, at the base of the Duckmantian, sediment was briefly introduced from the west as a far-field manifestation of Alleghanian tectonism. Finally, continued uplift of the Variscan mountain belt to the south of the UK led to establishment of northward-directed transport systems that reached the northern Pennine Basin in the mid-Bolsovian, leading totermination of supply from the Pennine River.