Page 62 - An Atlas of Carboniferous Basin Evolution in Northern England

Palaeogeography and fades evolution 41

former carbonate platforms to the southeast being sites of non-deposition or condensed over much of the East Midlands area. However, thick sequences are Kinderscoutian (Steele 1988) and thin shallow water sandstones and
erosion (e.g. Holme High) (Fig. 33). Southerly-derived, proximal turbidites, reported from the central Gainsborough Trough (c. 280 m from Scaftworth-2) mudstones typify the entire Kinderscoutian of North Wales and the Lancashire
with quartzitic petrography, continued to accumulate at the head of the and Goyt Trough (up to 200 m; Figs 2 and 35). Minor volcanism and tuffs may shelf area. The remaining topographic lows to be infilled following the
Gainsborough Trough and Widmerpool Gulf, with only minor distal turbidites be of Chokierian-Alportian age in the vicinity of the Long Clawson-1 borehole deposition of the Kinderscout delta lay to the south in Derbyshire, north
entering from the north. Proximal turbidites and minor slumps developed in the Widmerpool Gulf (Figs 2 and 35). Mudstones and siltstones, with minor Staffordshire and the East Midlands and to the west in the Manx-Furness
around the margins of the East Midland basins, perhaps indicating some minor turbiditic sandstones, dominated deposition in the North Staffordshire Basin Basin (Fig. 37).
extensional fault movements in the Pendleian. The former Dinantian shelf (e.g. Lower and Middle Churnet Shales). By early Marsdenian times (Fig. 38), the Kinderscout delta was effectively
areas became sediment-starved platforms or areas of non-deposition. Minor abandoned, leading to the R. gracile maximum flooding surface. The
quartzose deltas formed on the shallow shelf areas along the Mercian Massif sedimentary facies and sequence stratigraphy of the Marsdenian have been
shoreline. Sequence LC1c: post-rift ( Kinderscoutian-early West- studied in detail over the East Midlands area (Church & Gawthorpe 1994,
phalian A) 1997; Fig. 15), and in parts of the adjacent outcrops in Derbyshire and North
Staffordshire (Jones & Chisholm 1997) and the central Pennines (e.g. Wignall
Sequence LClb: post-rift (late Pendleian-Alportian) The influx of coarse-grained sediment from the north recommenced some time & Maynard 1996). Major channel systems were established from the east and
during the early to mid Kinderscoutian leading to major deltaic progradation NE across the East Midlands area by the middle Marsdenian forming the
After the major turbidite-fronted delta advance across the Bowland Basin and infilling of the northern part of the Pennine Basin (Figs 36 and 37). The Ashover-Roaches delta. This represents the last deep water turbidite-fronted
during the early Pendleian (LCIa), the Arnsbergian was a time of turbidite whole Kinderscoutian stage exceeds 500 m in north Derbyshire in contrast to a system and infilled the Widmerpool Gulf axially from the SE (Fig. 38). The
sandstone and mudstone deposition over much of the central Pennines (Fig. mere 30 m in the Woodland borehole on the Alston Block. Roaches Grit of north Staffordshire represents the corresponding turbidite
34). Interbedded delta-top sandstones and mudstones of the Roeburndale Grit During the early part of LClc (early-mid Kinderscoutian) deposition of deposits on the delta front in the deep Goyt Trough (Jones 1980; Jones &
Group were deposited in the Lancaster Fells and the Silsden Moor Grits Yoredale-type facies persisted in the Northumberland Trough-Alston Block Chisholm 1997) (Fig. 38). Following progradation of this delta, all of the
prograded southwards from the Askrigg Block into the Leeds-Bradford area area, with quartzose sandstones containing brachiopods and shelly fauna sediment starved basinal areas in northern England had been infilled.
(Arthurton et al. 1988). To the south and west Lower Sabden Shales deposition indicative of very shallow water developed on the southern edge of the Alston Across the Gainsborough Trough, Ashover Grit equivalents included coarse
was dominant, as encountered in outcrops and also in boreholes (e.g. Croxteth, Block in Wharfedale-Nidderdale (e.g. Cayton Gill Shell Bed). In contrast, pebbly channel sandstones (e.g. Trumfleet Grit) with sedimentation dominated
Upholland, Heywood, Fletcher Bank and Holme Chapel; Figs 2 and 34). coarse-grained fluvial sandbodies developed across the Askrigg Block, for by shallow-water delta deposition (Steele 1988) (Fig. 38). In general, the East
Across the Northumberland Trough and the Alston and Askrigg Blocks, example the Libishaw and Brimham Grits (Ramsbottom et al. 1978) (Fig. 36). Midlands Platform succession is thinner, with few thin fluvial channel
Yoredale-type sedimentation persisted throughout the Arnsbergian (e.g. These prograded over the Craven Fault Zone as various deltaic lobes, such as sandstones that grade westwards into pro-delta mudstones and siltstones.
Leeder et al. 1989; Fig. 34). Sedimentation kept pace with subsidence in the the Cobden and Caley Crags Grits of the Lancaster Fells and West Yorkshire Abandonment of the Ashover-Roaches delta system is interpreted to have
Stainmore Trough as evidenced from increased thickness in the absence of any (Ramsbottom 1974; Ramsbottom et al. 1978; Fig. 36). Mudstone deposition resulted from relative sea-level rise, culminating in the R. superbilinque
major facies variation. Fluvio-deltaic sandbodies (e.g. Thornborough, Grind- persisted across most of the Pennine Basin from Lancashire to the East maximum flooding surface (Church & Gawthorpe 1994; Jones & Chisholm
stone, Botany, Red Scar Grits) are interbedded with shallow marine mudstones Midlands (e.g. Upper Sabden and Upper Churnet Shales), including local 1997; Fig, 15).
and limestones, reflecting the continued influence of glacio-eustatic sea-level turbidites (e.g. Mam Tor Sandstones) (Fig. 36). By late Marsdenian times shallow-water delta-top conditions were estab-
fluctuations on high-frequency sequence development. The Cumbrian non- By late Kinderscoutian times (Fig. 37), the southward advance of a major lished across most of northern England (Fig. 39). The late Marsdenian and
depositional/erosional high was onlapped by thin or condensed marine delta from the north dominated northern England. The Kinderscout delta Yeadonian, like much of the Namurian, is characterized by high frequency
mudstones and interbedded deltaic siliciclastics of the Upper Hensingham complex comprises a number of high frequency sequences, the oldest cyclicity, comprising goniatite-bearing marine mudstones passing upwards
Group (Fig. 34). dominated by basin floor and slope turbidites of the Mam Tor Sandstone through delta-front mudstones and siltstones, into mouth bar and fluvial
Across the central Pennines and East Midlands areas, non-deposition or and Shale Grit and equivalents. Palaeocurrents within these initial coarse- channel sandstones and delta-top deposits associated with coals and
erosion of earlier Dinantian carbonate shelf areas persisted, such as the Holme grained basinal sediments highlight the reduction in inherited bathymetric palaeosols. Typically these 'shallow water delta' cycles are 10 to 50 m thick
High and Askern-Spital High, where no pre-Kinderscoutian sediments are control as the sediment starved basinal areas were infilled. For example, initial in the East Midlands and each cycle is characterized by a major fluvial
proven. Thin, condensed mudstone-dominated sequences onlap these shelf turbidites of the Mam Tor Sandstone flow to the west parallel to the trend of sandbody such as the Chatsworth Grit-Huddersfield White Rock (e.g. Figs 15
areas. The thickest Arnsbergian sections occur in the previously starved and the Dinantian carbonate platform margin, whereas towards the top of the and 39), Lower Haslingden Flags, and Rough Rock-Upper Haslingden Flags.
thermally subsiding Gainsborough Trough, Edale Gulf, Widmerpool Gulf and formation the flow is dominantly to the south across the underlying syn-rift The major sediment transport direction was to the west and SW, although the
Goyt Trough depocentres (Fig. 34). Turbidites and shallow marine siliciclastics basin margin (Allen 1960). The turbidites were followed by slope deposits of syn-rift basin morphology continued to influence transport pathways with
derived from the Mercian Massif to the south were channelled longitudinally the Grindslow Shales which form a delta front coarsening-up package axial transport inferred along the Widmerpool Gulf into the Yeadonian
along the southern-most gulf areas, as proven in the Rempstone-1 and Duffield underlying the main fluvial sandbodies of the lower Kinderscout Grit. (Walker (Church & Gawthorpe 1997) (Fig. 39). However, sediment supply from the
boreholes (Figs 2 and 34). 1966; Collinson 1968; McCabe 1978). Although the Edale Shale to Lower west and northwest occurred during deposition of the Yeadonian Lower and
The Chokierian-Alportian stages are both poorly represented (condensed) Kinderscout Grit succession was originally interpreted as a series of genetically Upper Haslingden Flags (Collinson & Banks 1975) and provenance studies
across most of northern England and North Wales (Fig. 35). Across the related environments from basinal through turbidite fans and slope to delta suggest a different source area to the northern source that had dominated up
Northumberland Basin and southwards to the Craven faults, Chokierian/ top, several major candidate sequence boundaries and marine flooding surfaces until now (e.g. McLean & Chisholm 1996). This westerly source area became
Alportian sediments comprise thin mudstones or are absent or unrecognised. within this succession suggest the presence of a number of depositional dominant during the overlying Westphalian A (e.g. Hallsworth & Chisholm
In the Colsterdale area, this interval is represented by mature palaeosols sequences (e.g. Hampson 1997). In contrast to the Lower Kinderscout Grit, the 2000).
(ganister), intercalated with minor marine limestones and mudstones. In Upper Kinderscout Grit is a sheet-like sandbody that was deposited following It is generally accepted that these cycles result from high frequency glacio-
Yorkshire, these stages are represented by less than 30 m of mudstones and a short-lived abandonment, represented by the Butterly Marine Band eustatic sea-level changes (e.g. Ramsbottom 1977; Leeder 1988; Holdsworth &
siltstones in the Cowling area and a slightly greater thickness in Wharfedale maximum flooding surface. The Upper Kinderscout Grit may be traced Collinson 1988; Maynard & Leeder 1992; Church & Gawthorpe 1994;
(Fig. 35). In the latter, fluvial sandstones of the Upper Follifoot Grit up to 18 northwards into the Upper Brimham Grits (McCabe 1977) (Fig. 37). Hampson et al. 1995, 1997). The goniatite-bearing marine mudstones (marine
m thick occur at the top of the succession, heralding the subsequent The various high-frequency sequences that comprise the Kinderscout Grits bands) reflect maximum flooding surface condensed sections and the overlying
progradation of the Kinderscout delta system. Similar sandstones have been effectively filled the Pennine and other Central Province basins by the end of delta-front to delta-top succession, progradation of the highstand systems
identified in boreholes in the Cleveland Basin (e.g. Kirby Misperton-1; Figs 2 the Kinderscoutian resulting in widespread shallow water and delta-top tract. Many of the major fluvial sandbodies, e.g. the Rough Rock, display
and 35). conditions in these areas (Fig. 37). Minor, shallower-water, coarsening upward marked incision into underlying sequences and are interpreted as incised valley
Where present at all, Chokierian-Alportian sedimentation is thin and deltaic cycles occurred across the Gainsborough Trough area throughout the fills (Church & Gawthorpe 1994, 1997; Fig. 15).