Stratigraphic significance of calcareous microfossils from the Lower Carboniferous rocks of the Skipton area, Yorkshire

Abstract

SummaryAssemblages of calcareous foraminifera and algae have been examined in thin sections of Dinantian limestones from the Skipton, Broughton, Hetton, Eshton, Swinden and Lothersdale anticlines in the Craven Lowlands. Provisional identifications are listed for each assemblage and a correlation of the rock successions is suggested. The assemblages range from late Tournaisian to late Viséan in age, in terms of the Belgian divisions, and from Courceyan to Asbian in terms of the new chronostratigraphic stages of George et al. (1976).

Revision of the Dinantian stratigraphy of the Craven Basin, N England

“…The more successful use of goniatites in time correlation is restricted to the higher parts of the sequence, where Bisat (1928) founded the locally useful Cracoean (B) and Bollandian (P) stages, each subdivided into zones. The distribution of the foraminifera and other stratigraphically important calcareous microfossils seen in thin section was described for the rock units of the eastern area by Fewtrell & Smith (1978), while time-correlation based on this information, but avoiding the establishment of zones, was given elsewhere (Smith & Fewtrell, 1979). The availability and diversity of both foraminifera and conodonts in the limestones of the Craven Basin has already been demonstrated by Fewtrell & Smith (1978) and Metcalfe (1978).…”

“…It is represented in the eastern Craven area mainly by the Skibeden Shales-with-Limestones (Hudson & Mitchell, 1937). A useful reference section for the eastern area is the abortive New Quarry, Hambleton (SE 045 533), which exposes 85 m of Skibeden Shales-with-Limestone overlain by 29 m of strata referred to as the Skibeden Limestone by Fewtrell & Smith (1978). The type section is taken as that exposed in Worston Brook between SD 772 426 and SD 780 423 (Earp et al 1961, p. 58).…”

Conodont Faunas and Age of the Raygill Quarry Limestones (Embsay Limestone), Lothersdale, Yorkshire

“…The base of the Gnathodus commutatus Zone occurs at or below 27 metres from the top of the section. Fewtrell and Smith (1978) recorded archaediscid foraminifera from the then 42 metres of strata exposed at Raygill Quarry and suggested that the section was of Vlb to V2a age (Arundian). This was younger than the previously assigned ?C age (Earp et ah 1961).…”

“…Fewtrell and Smith (1978) recorded the first archaediscids 22 metres below the top of the Embsay Limestone at Halton East Quarry and recognised large scale cross-bedding and oolites in the top 10 metres. A tentative correlation between the Raygill Quarry limestones and the top part ofthe Embsay Limestone was suggested by Fewtrell and Smith (1978, p. 268).…”

“…Earp et al (1961) briefly described the limestones in the quarry and recorded 30 metres of strata which they included in the Chatburn Limestone Group (but did not specifically name). Fewtrell and Smith (1978) recorded 42 metres of exposed strata and noted that the section formed an overall shallowing upwards sequence from planar, fine grained, bioclastic limestones and shales to cross-bedded limestones with less shale and then clean coarse limestones with large scale cross-bedding and oolites in the upper 10 metres. This shallowing upwards sequence is seen in the upper part of the limestone (Fig.…”