Page 57 - An Atlas of Carboniferous Basin Evolution in Northern England

36 Chapter 4

Fig. 31. Schematic regional north-south cross section illustrating the diachronous development of basin-filling turbidites and fluvio-deltaic sandstones across the Pennine Basin from the Bowland Basin in the north to the Widmerpool Gulf/Goyt Trough in the south. Note that the first
phase of coarse-clastic infill is dominated by turbidites in each major depocentre. After Collinson (1988).

grade from proximal talus through coarse grainstone turbidites and mass reflect high frequency glacio-eustatic sea-level changes, like the carbonate related faunal variations. The record of palynofloras belonging to the ME
flows, into hemipelagic and pro-delta mudstones of the lower slope and basin. cyclicity developed in shelf settings to the south. Subzone (Clayton et al. 1977) of the NM Zone (Neves et al. 1912) is consistent
These slope and basinal fades associations are well developed in the Bowland with the late Asbian age assigned to the base of the sequence (Ebdon et al.
Basin (e.g. Gawthorpe 1986, 1987a, b; Riley 1990) and imaged on seismic from 1990).
the adjacent subsurface (Evans & Kirby 1999). Shallow-marine shelf limestones accumulated on the East Midlands
Deltaic conditions prevailed in the northeast with the development of the Sequence EC5: syn-rift III (late Asbian—early Brigan- Platform and Hathern Shelf (Fig. 29). In the basinal setting borehole evidence
Yoredale delta system, with pro-delta mudstones providing some potential tian) (Ratcliffe-on-Soar-1; Fig. 14) indicates that EC5 consists of a monotonous
hydrocarbon source rocks in the Northumberland/Solway and Cleveland series of calcareous mudstones and thin dolomitic limestones (Fig. 29). As with
basins (Fig. 28). The delta system had advanced considerably southwards, Renewed tectonic activity in late Asbian times again reactivated and rotated earlier rift phases, debris flow horizons, carbonate breccias and sedimentary
infilling much of the Northumberland and Cleveland basins with cyclical fault blocks causing inundation of the shelf margins, footwall erosion and slides are present (e.g. Bowland Basin; Gawthorpe 1986, 19870). During EC5
deltaic siliciclastics. Cyclicity in the mixed carbonate-clastic Yoredales slumping and boulder bed deposition in hanging-wall settings within the times siliciclastics advanced further south, reaching the Bowland Basin for the
involved fluvial channel belts and overbank deposits with minor coals, and Bowland Basin and the main basins of the East Midlands (Fig. 29). The exact first time to form the pro-delta Lower Bowland Shale (Fig. 29). Shallow-water
interbedded marine limestones and mudstones. The cyclicity is interpreted to timing of this end-Asbian event is difficult to ascertain due to rapid facies- carbonates in the footwall of the Pendle Fault continuded to be restricted to