Distribution of the Geological Conservation Review sites for the Ludlow Series, set against the palaeogeographical elements of Silurian Britain.

Geological cross-sections drawn by Sir Roderick Murchison for a lecture given in 1852 to the Ludlow Natural History Society and now housed in Ludlow Museum. The upper section runs from east to west, from the Cambrian of Wales, through Murchison’s ‘Lower Silurian’ (now Ordovician) of the Stiperstones area of Shropshire and beyond to Ludlow Castle, to the Old Red Sandstone and, ultimately, the Carboniferous of the Clee Hills to the north-east of Ludlow. The lower section runs north–south, from Bromfield just north of Ludlow, across the Ludlow Anticline and into Herefordshire.

Location of Pitch Coppice, Wigmore Road, near Ludlow Quarry, Shropshire (after Lawson and White, 1989).

The boundary stratotype section for the base of the Ludlow Series and the base of the Gorstian Stage at Pitch Coppice, Wigmore Road, near Ludlow (Holland et al., 1963; diagram after Lawson and White, 1989; both papers describe lithological divisions A–F).

The boundary stratotype section for the base of the Ludlow Series and the base of the Gorstian Stage at Pitch Coppice, Wigmore Road, near Ludlow, Shropshire (for lithologies see Figure 5.4). (Photo: Ken J. Dorning.)

Map of the geology south-west of Ludlow, showing GCR sites along the Wigmore Road and elsewhere in the eastern part of the Ludlow Anticline (after Holland et al., 1963; Lawson, 1977; Lawson and White, 1989).

Geology of the section along the Goggin Road, Mortimer Forest, near Ludlow, Shropshire (after White and Lawson, 1978, with modifications from Siveter et al., 1989 and Sutherland, 1994).

Middle Elton Formation at White and Lawson’s (1978) locality 16–18 along the Goggin Road, Mortimer Forest, near Ludlow, Shropshire: mudstones containing bentonites (whitish horizons). (Photo: Derek J. Siveter.)

The acritarch Multiplicisphaeridium variable (Lister, 1970) Dorning, 1981 (left, × 1050) and the chitinozoan Ancyrochitina gogginensis Sutherland, 1994 (right, × 320), from the Lower Elton Formation, Goggin Road, Mortimer Forest, near Ludlow. (Photos: G. Mullins.)

Geology of Sunnyhill Quarry and contiguous trackside section, Mary Knoll Valley, Mortimer Forest, near Ludlow, Shropshire (after White and Lawson, 1978, with modifications from Siveter et al., 1989; localities 14 and 31 are repositioned after Lawson and White, 1989, p. 90, fig. 58).

Log through the boundary stratotype section for the base of the Ludfordian Stage at Sunnyhill Quarry, Mary Knoll Valley, Mortimer Forest, near Ludlow, Shropshire (after Holland et al., 1963, A–I = lithological divisions; and Lawson and White, 1989, C5–14 = combined locality and collection numbers).

The boundary stratotype section for the base of the Ludfordian Stage at Sunnyhill Quarry, Mary Knoll Valley, Mortimer Forest, near Ludlow, Shropshire. The recessed horizon is ‘C12’ of Figure 5.11. (Photo: David J. Siveter.)

Flaggy, calcareous siltstones; Lower Leintwardine Formation, east part of Sunnyhill Quarry, Mary Knoll Valley, Mortimer Forest, near Ludlow, Shropshire. (Photo: David J. Siveter.)

Geology of the section along the Deer Park Road, Mortimer Forest, near Ludlow, Shropshire (after White and Lawson, 1978 with modifications from Siveter et al., 1989).

Location and general stratigraphical position of localities at GCR sites The Whitcliffe and Ludford Lane and Corner, Ludlow, Shropshire (after Holland et al., 1963; modified from Siveter et al., 1989).

Geology of an area adjacent to the riverside path on the Whitcliffe, Ludlow, Shropshire, which shows the basal boundary stratotypes and body stratotypes for the Upper Leintwardine and Lower Whitcliffe formations (after Holland et al., 1963; modified from Siveter et al., 1989); see also Figures 5.17–5.19.

The boundary stratotype section for the base of the Upper Leintwardine Formation (see Figures 5.16 and 5.18), adjacent to the riverside path on the Whitcliffe, Ludlow, Shropshire (after Holland et al., 1963; modified from Siveter et al., 1989).

The Lower Leintwardine Formation and the basal boundary stratotypes and body stratotypes for the Upper Leintwardine and Lower Whitcliffe formations (see Figures 5.16, 5.17 and 5.19), adjacent to the riverside path on the Whitcliffe, Ludlow, Shropshire. (Photo: David J. Siveter.)

The boundary stratotype section for the base of the Lower Whitcliffe Formation (see Figures 5.16, 5.18), adjacent to riverside path on the Whitcliffe, Ludlow, Shropshire (after Holland et al., 1963; modified from Siveter et al., 1989).

The boundary stratotype section for the base of the Upper Whitcliffe Formation, at the old quarry on the Whitcliffe (see Figure 5.21), Ludlow, Shropshire (after Holland et al., 1963; modified from Siveter et al., 1989).

The Lower Whitcliffe Formation and the basal boundary stratotype and body stratotype for the Upper Whitcliffe Formation, at the old quarry on the Whitcliffe, Ludlow, Shropshire. (Photo: David J. Siveter.)

Looking north-east from Whitcliffe Common (SO 5053 7430, locality 3.1a of Siveter et al., 1989); sited on the axial trace of the Ludlow Anticline, across Ludlow, Shropshire towards Titterstone Clee Hill (Devonian–Carboniferous). The regional dip and younging direction is north-west to south-east. (Photo: David J. Siveter.)

The geology between GCR sites at Bow Bridge and Burrington, in the western part of the northern limb of the Ludlow Anticline (after Holland et al., 1963 and Lawson and White, 1989).

The location of the basal stratotype section of the Middle Elton Formation, at Nunfield Gutter, near Burrington, in the Ludlow Anticline (from Holland et al., 1963). The letters refer to parts of the section as described by Holland et al. (1963).

Geology of Elton Lane, Herefordshire, in the region of the Ludlow Anticline (after Lister, 1970; see also Wood, 1900 and Williams and Prentice, 1958).

Location of the basal boundary stratotype locality for the Lower Bringewood Formation, Mary Knoll Valley, Mortimer Forest, Shropshire (after Holland et al., 1963).

The geology in the vicinity of GCR sites Church Hill Quarry and Mocktree Quarries, Leintwardine area, Herefordshire (after Whitaker, 1962).

Schematic reconstruction (not to scale) of an idealized submarine channel-head of basal Ludfordian times (after Whitaker, 1962). Data from several channels. Note that down-cutting is more severe down-channel.

Carbonate boulder (Bringewood Group) in channel-fill deposits (calcareous siltstones, Lower Leintwardine Formation) of the Church Hill Channel, Trippleton, near Leintwardine, Herefordshire. (Photo: David J. Siveter.)

Several specimens of the starfish Sturtzaster marstoni (Salter); slab from the Leintwardine Group, Church Hill Quarry, near Leintwardine, Herefordshire (Grindrod Collection, Oxford University). (Photo: Derek J. Siveter.)

The geology of the vicinity of Mocktree Quarries near Leintwardine, Herefordshire (after Whitaker, 1962).

South-east face of Mocktree Quarries, near Leintwardine, Herefordshire, displaying Lower Leintwardine siltstones infilling the Mocktree submarine channel. This channel down-cuts, with a broad, gently curved base, into Basal Leintwardine Formation siltstones (0.7 m remaining in the centre of the channel), which lie above the Upper Bringewood Formation limestones occupying the lower part of the section (from below base of tree at centre right). Person at bottom left is J.H.McD. Whitaker. (Photo: David J. Siveter.)

Block diagram, not to scale, illustrating the possible shelf edge and Welsh Basin slope in the Lentwardine–Lingen area at the beginning of Ludfordian time (after Whitaker, 1994). In the south-west, where the boulder bed is developed as a debris flow downslope from the postulated slide scar, places where Elton beds are not fully stripped off are not necessarily in their correct positions, nor is the Coalbrookdale ‘window’ where Lower Leintwardine erosion has cut right through the Wigmore Rolls Formation into the top of the Coalbrookdale Formation.

The geology of Aymestrey Quarries, Beechenbank Wood, Aymestrey, Herefordshire (after Lawson, 1973b; modified from Siveter et al., 1989).

Comparative vertical sections in the Aymestrey area, to show east–west changes in facies and thickness of the Upper Bringewood Formation (after Lawson 1973b; modified from Siveter et al., 1989).

The Main Quarry at Aymestrey, Herefordshire, exposing limestones of the Upper Bringewood Formation and, near the top of the section, the flaggy calcareous siltstones of the overlying Lower Leintwardine Formation. (Photo: David J. Siveter.)

The geology of the Craven Arms area, Shropshire, showing the location of View Edge (after Siveter et al., 1989).

The quarries at View Edge, near Craven Arms, Shropshire: Upper Bringewood Formation carbonates containing abundant shell lags of the brachiopod Kirkidium knightii. (Photo: David J. Siveter.)

Measured section showing lithologies and faunas of the Upper Bringewood Formation at View Edge (after Watkins and Aithie, 1980).

The geology of the Upper Millichope area, Shropshire (modified from Shergold and Shirley, 1968).

Faunal profile of 15.8 m of Middle Elton Formation strata at Upper Millichope, Shropshire (modified from Watkins, 1979): the Glassia obovata Association of Watkins (1979).

The geology in the vicinity of Turner’s Hill, West Midlands (modified from Ball, 1951). Location of roads, buildings and quarries are shown as in 1951.

The Silurian succession at Turner’s Hill, West Midlands (modified from Ball, 1951).

Ludlow Series (Bringewood, Leintwardine and Whitcliffe groups) to basal PÍídolí Series, Woodbury Quarry, Abberley Hills, Worcestershire; the strata young from right to left, are overturned to the east and dip 70°–80°. (Composite photo: David J. Siveter, 1970.)

Gurney’s Quarry, Ledbury, Herefordshire: Much Wenlock Limestone Formation and the calcareous mudstones and siltstones of the overlying Lower Ludlow Formation. (Photo: Derek J. Siveter.)

Succession and correlation of the Silurian strata at Linton Quarry, Gorsley Inlier, Herefordshire (after Lawson, 1954; see also Cocks et al., 1971, 1992).

The concept of the ‘Gorsley topographical high’ of the Welsh Basin, as illustrated in the facies and thickness variations of the Leintwardine Group (early Ludfordian Stage) in a general south-west to north-east transect from the region of the Brookend Borehole, Gloucestershire, to Kerry, Powys (after Cherns, 1988).

The geology of the A4136 road section and adjacent area, near Longhope, Gloucestershire (after Lawson, 1955).

Calcareous siltstones with shelly fauna dominated by brachiopods (e.g. S. lunata, M. nucula and P. ludloviensis), Upper Longhope Beds, Longhope Hill (A4136 road), Gloucestershire. (Photo: David J. Siveter.)

The geology of the Wood Green area, Gloucestershire (after Lawson, 1955).

The geology of the area south of Perton, Woolhope Inlier, Herefordshire (after Squirrell and Tucker, 1960).

Upper Sleaves Oak Beds and Lower Bodenham Beds, Perton Quarry, Woolhope Inlier, Herefordshire. (Photo: David J. Siveter.)

The early vascular land plant Cooksonia pertoni Lang, 1937, from the PÍídolí Rushall Beds, small quarry at north end of Perton Lane, Woolhope Inlier, Herefordshire; the specimen is 15 mm long. (Photo: Dianne Edwards.)

Sketch maps showing the Silurian geology (upper Ludlow to lower PÍídolí) of the foreshore at Tites Point, near Purton, Gloucestershire (after Cave and White, 1971; Curtis, 1982).

The stratigraphy of the Ludlow to early PÍídolí series at Tites Point, near Purton, Gloucestershire (after Cave and White, 1971).

The geology in the vicinity of Brook House, near Llangybi, in the Usk Inlier, Gwent (after Walmsley, 1959).

Geological map of the Radnor Forest area, Powys, showing the location of GCR sites Meeting House Quarry and Mithil Brook and Cwm Blithus (after Woodcock and Tyler, 1993; based partly on Kirk, 1947, and Holland, 1959).

Position of Meeting House Quarry and Mithil Brook and Cwm Blithus, Powys, on a platform-basin transect showing lithostratigraphical formations of Gorstian age (after Woodcock and Tyler, 1993).

Laminated hemipelagites and homogeneous silty mudstones of the Llanbadarn Formation, Meeting House Quarry, Powys. (Photo: David J. Siveter.)

Reconstruction of the palaeoenvironment represented by the Ludlow Series Llanbadarn Formation at Meeting House Quarry, Powys (after Siveter et al., 1991): an off-shelf, slope facies assemblage associated with laminated hemipelagites and dominated by pelagic organisms; bottom waters and sediments were mostly poorly aerated. In general order of abundance the fossil taxa illustrated are: orthoconic nautiloids, monograptids, myodocope ostracods, pterineid and cardiolid bivalves and pisocrinid crinoids.

The geology in the vicinity of Mithil Brook and Cwm Blithus, mid-Powys (after Bailey and Woodcock, 1976; Siveter et al., 1989; Woodcock and Tyler, 1993).

Log of the slumped sequence in Cwm Blithus, mid-Powys (modified from Woodcock, 1976a; Woodcock and Tyler, 1993).

Slump folds affecting calcareous siltstones in the Bailey Hill Formation, Cwm Blithus, mid-Powys. (Photo: N.H. Woodcock.)

The geology of part of the south-east flanks of Beacon Hill, Powys (after Holland and Palmer, 1974).

The graptolite Bohemograptus bohemicus (Boucek) (from Holland and Palmer, 1974): left, from the Long Mountain Siltstone Formation, Long Mountain, Powys (approximately × 2); right, from the Knucklas Castle Formation, Beacon Hill, Powys (× 6).

Silurian succession of the Sawdde Gorge, Carmarthenshire, showing lithologies, generalized sea-level curve and ranges of selected fossils (after Siveter et al., 1989).

Steeply dipping, ripple-marked bedding planes of the highest beds of the Black Cock Formation (centre), overlain (upper right) by the Carn Powell Member, north side of the southern quarry at Cwar Glâs, Sawdde Gorge, Carmarthenshire. (Photo: David J. Siveter.)

Distribution of the Dinas Brân Beds at Dinas Brân, near Llangollen (after Bell, 1990; with minor additions from Hains and Davies, 1991). For details of logged section see Figure 5.69.

Log of the Dinas Brân Beds in the eastern moat of Castell Dinas Brân (see Figure 5.68), near Llangollen (after Bell, 1990): low-angle cross-bedded sandstones interbedded with bioturbated siltstones.

Geological map in the vicinity of Llangollen, showing the location of the GCR sites Clogau Quarry and Dinas Brân (after Wills and Smith, 1922, with minor additions to the fault pattern from Hains and Davies, 1991).

Part of the Slab Beds, Glyn-Dyfrdwy Group, Ludlow Series, at Clogau Quarry, near Llangollen. (Photo: A3125, looking NNW, July 1925; courtesy of the British Geological Survey.)

Ty’n-y-Ffordd Quarry near Llangerniew, showing contorted and fragmented (disturbed) beds of the Elwy Group cutting down into the silty mudstones and ribbon-banded mudstones of the Upper Nantglyn Flags Group; note hammer, at bottom right, for scale. (Photo: L1601, reproduced by kind permission of the Director, British Geological Survey, © NERC.)

Generalized succession of the Elwy Group in the Llangerniew area (after Warren et al., 1984). The local formations are after Jones (1937).

Lithological log of the Yewbank Formation, Coniston Group, in the northern Tebay roadcut, Cumbria, between numbered fence post 33 at NY 6098 0194 and post 66 at NY 6102 0206 (modified from King, 1992). The prominent lithofacies (B, C, D and E; see text) follow the scheme of Pickering et al. (1989).

Coniston Group, Gorstian Stage, Tebay Cutting, Cumbria. The photograph shows laminated hemipelagic mudstones with intercalated turbidite, comprising a silt–mud interlaminated base overlain by homogenous mud; dark interval on staff = 10 cm. (Photo: N.H. Woodcock.)

Evolution of lithostratigraphical nomenclature in the Kendal Group, upper part of the Windermere Supergroup (after Lawrence et al., 1986). This nomenclature is relevant to Ludlow Series sites at Hills Quarry and Benson Knott, and to the PÍídolí site at The Helm, Cumbria.

Diagram illustrating the diachroneity of the lithostratigraphical units of the Kendal Group (after King, 1994).

Representative log of the Underbarrow Formation at Hills Quarry, Cumbria (modified from King, 1992). Beds are assigned to one of three lithofacies (see text).

The Underbarrow Formation at Hills Quarry, Cumbria. (Photo: David J. Siveter.)

Representative log of the Kirkby Moor Formation at Benson Knott, Cumbria (at SD 5465 9418; modified from King, 1992). Beds are assigned to lithofacies 2 to 4 (see text); lithofacies 2 and 3 match similar facies in the Underbarrow Formation (see GCR site report for Hills Quarry). At Benson Knott lithofacies 3 and 4 are prominently developed but lithofacies 2 (which dominates in the Underbarrow Formation) is subordinate.

Hypothetical reconstruction of the northern margin of the Lake District Basin and its associated depositional environments, for formations spanning the Ludfordian–early PÍídolí time interval (after King, 1992). No absolute depths or scale are implied.

The Kirkby Moor Formation at Benson Knott, Cumbria. (Photo: N.H. Woodcock.)